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Updated: 3 hours 14 min ago

Google Play services 7.0 - Places Everyone!

Tue, 03/03/2015 - 02:26

Posted by Ian Lake, Developer Advocate

Today, we’re bringing you new tools to build better apps with the rollout of Google Play services 7.0. With this release, we’re delivering improvements to location settings experiences, a brand new API for place information, new fitness data, automatic integration of AdMob and Google Analytics, Google Play Games, and more.

Location Settings Dialog

While the FusedLocationProviderApi combines multiple sensors to give you the optimal location, the accuracy of the location your app receives still depends greatly on what settings are enabled on the device (e.g. GPS, wifi, airplane mode, etc). In Google Play services 7.0, we’re introducing a standard mechanism to check that the necessary location settings are enabled for a given LocationRequest to succeed. If there are possible improvements, you can display a one touch control for the user to change their settings without leaving your app.

This API provides a great opportunity to make for a much better user experience, particularly if location information is critical to the user experience of your app such as was the case with Google Maps when they integrated the Location Settings dialog and saw a dramatic increase in the number of users in a good location state.

Places API

Location can be so much more than a latitude and longitude: the new Places API makes it easy to get details from Google’s database of places and businesses. The built-in place picker makes it easy for the user to pick their current place and provides all the relevant place details including name, address, phone number, website, and more.

If you prefer to provide your own UI, the getCurrentPlace() API returns places directly around the user’s current location. Autocomplete predictions are also provided to allow a low latency search experience directly within your app.

You can also manually add places with the addPlace() API and report that the user is at a particular place, ensuring that even the most explorative users can input and share their favorite new places.

The Places API will also be available cross-platform: in a few days, you’ll be able to apply for the Places API for iOS beta program to ensure a great and consistent user experience across mobile platforms.

Google Fit

Google Fit makes building fitness apps easier with fitness specific APIs on retrieving sensor data like current location and speed, collecting and storing activity data in Google Fit’s open platform, and automatically aggregating that data into a single view of the user’s fitness data.

In Google Play services 7.0, the previous Fitness.API that you passed into your GoogleApiClient has now been replaced with a number of APIs, matching the high level set of Google Fit Android APIs:

  • SENSORS_API to access raw sensor data via SensorsApi
  • RECORDING_API to record data via RecordingApi
  • HISTORY_API for inserting, deleting, or reading data via HistoryApi
  • SESSIONS_API for managing sessions via SessionsApi
  • BLE_API to interact with Bluetooth Low Energy devices via BleApi
  • CONFIG_API to access custom data types and settings for Google Fit via ConfigApi

This change significantly reduces the memory requirement for Google Fit enabled apps running in the background. Like always, apps built on previous versions of Google Play services will continue to work, but we strongly suggest you rebuild your Google Fit enabled apps to take advantage of this change.

Having all the data can be an empowering part of making meaningful changes and Google Fit is augmenting their existing data types with the addition of body fat percentage and sleep data.

Google Mobile Ads

We’ve found integration of AdMob and Google Analytics a powerful combination for analyzing how your users really use your app since we launched Google Analytics in AdMob last year. This new release enables any Google Mobile Ads SDK implementation to automatically get Google Analytics integration giving you the number of users and sessions, session duration, operating systems, device models, geography, and automatic screen reporting without any additional development work.

In addition, we’ve made numerous improvements across the SDK including ad request prefetching (saving battery usage and improving apparent latency) and making the SDK MRAIDv2 compliant.

Google Play Games

Announced at Game Developers Conference (GDC), we’re offering new tools to supercharge your games on Google Play. Included in Google Play services 7.0 is the Nearby Connections API, allowing games to seamlessly connect smartphones and tablets as second-screen controls to the game running on your TV.

App Indexing

App Indexing lets Google index apps just like websites, enabling Google search results to deep-link directly into your native app. We've simplified the App Indexing API to make this integration even easier for you by combining the existing view()/viewEnd() and action()/end() flows into a single start() and end() API.

Changes to GoogleApiClient

GoogleApiClient serves as the common entry point for accessing Google APIs. For this release, we’ve made retrieval of Google OAuth 2.0 tokens part of GoogleApiClient, making it much easier to request server auth codes to access Google APIs.

SDK Coming Soon!

We will be rolling out Google Play services 7.0 over the next few days. Expect an update to this blog post, published documentation, and the availability of the SDK once the rollout is completed.

To learn more about Google Play services and the APIs available to you through it, visit the Google Services section on the Android Developer site.

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Categories: Programming

New Tools to Supercharge Your Games on Google Play

Mon, 03/02/2015 - 19:29

Posted by Greg Hartrell, Senior Product Manager of Google Play Games

Everyone has a gaming-ready device in their pocket today. In fact, of the one billion Android users in more than 190 countries, three out of four of them are gamers. This allows game developers to reach a global audience and build a successful business. Over the past year, we paid out more than $7 billion to developers distributing apps and games on Google Play.

At our Developer Day during the Game Developers Conference (GDC) taking place this week, we announced a set of new features for Google Play Games and AdMob to power great gaming. Rolling out over the next few weeks, these launches can help you better measure and monetize your games.

Better measure and adapt to player needs

“Player Analytics has helped me hone in on BombSquad’s shortcomings, right the ship, and get to a point where I can financially justify making the games I want to make.”

Eric Froemling, BombSquad developer

Google Play Games is a set of services that help game developers reach and engage their audience. To further that effort, we’re introducing Player Analytics, giving developers access to powerful analytics reports to better measure overall business success and understand in-game player behavior. Launching in the next few weeks in the Google Play Developer Console, the new tool will give indie developers and big studios better insight into how their players are progressing, spending, and churning; access to critical metrics like ARPPU and sessions per user; and assistance setting daily revenue targets.

BombSquad, created by a one-person game studio in San Francisco, was able to more than double its revenue per user on Google Play after implementing design changes informed during beta testing Player Analytics.

Optimizing ads to earn the most revenue

After optimizing your game for performance, it’s important to build a smarter monetization experience tailored to each user. That’s why we’re announcing three important updates to the AdMob platform:

  • Native Ads: Currently available as a limited beta, participating game developers will be able to show ads in their app from Google advertisers, and then customize them so that users see ads that match the visual design of the game. Atari is looking to innovate on its games, like RollerCoaster Tycoon 4 Mobile, and more effectively engage users with this new feature.
  • In-App Purchase House Ads Beta: Game developers will be able to smartly grow their in-app purchase revenue for free. AdMob can now predict which users are more likely to spend on in-app purchases, and developers will be able to show these users customized text or display ads promoting items for sale. Currently in beta, this feature will be coming to all AdMob accounts in the next few weeks.
  • Audience Builder: A powerful tool that enables game developers to create lists of audiences based on how they use their game. They will be able to create customized experiences for users, and ultimately grow their app revenue.

"Atari creates great game experiences for our broad audience. We're happy to be partnering with Google and be the first games company to take part in the native ads beta and help monetize games in a way that enhances our users' experience."

Todd Shallbetter, Chief Operating Officer, Atari

New game experiences powered by Google

Last year, we launched Android TV as a way to bring Android into the living room, optimizing games for the big screen. The OEM ecosystem is growing with announced SmartTVs and micro-consoles from partners like Sony, TPVision/Philips and Razer.

To make gaming even more dynamic on Android TV, we’re launching the Nearby Connections API with the upcoming update of Google Play services. With this new protocol, games can seamlessly connect smartphones and tablets as second-screen controls to the game running on your TV. Beach Buggy Racing is a fun and competitive multiplayer racing game on Android TV that plans to use Nearby Connections in their summer release, and we are looking forward to more living room multiplayer games taking advantage of mobile devices as second screen controls.

At Google I/O last June, we also unveiled Google Cardboard with the goal of making virtual reality (VR) accessible to everyone. With Cardboard, we are giving game developers more opportunities to build unique and immersive experiences from nothing more than a piece of cardboard and your smartphone. The Cardboard SDKs for Android and Unity enable you to easily build VR apps or adapt your existing app for VR.

Check us out at GDC

Visit us at the Google booth #502 on the Expo floor to get hands on experience with Project Tango, Niantic Labs and Cardboard starting on Wednesday, March 4. Our teams from AdMob, AdWords, Analytics, Cloud Platform and Firebase will also be available to answer any of your product questions.

For more information on what we’re doing at GDC, please visit g.co/dev/gdc2015.

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Categories: Programming

A New Way to Promote Your App on Google Play

Thu, 02/26/2015 - 14:05

Posted by Michael Siliski, Product Management Director, Google Play

Google Play now reaches more than 1 billion people on Android devices in more than 190 countries, helping a growing number of developers like you build successful global businesses. In fact, in the past year, we paid more than $7 billion to developers distributing apps and games on Google Play. We remain as committed as ever to making Google Play the best place to find great apps, games and other entertainment.

App discovery plays a critical role in driving your continued success, and over the past year Google has provided best practices to enhance app discovery and engagement, as well as app promotion tools to get the most out of search and display advertising for developers. We are always looking for new ways to help you get your apps in front of potential new users. That’s why, in the next few weeks, we will begin piloting sponsored search results on Google Play, bringing our unique expertise in search ads to the store.

With more than 100 billion searches every month on Google.com, we’ve seen how search ads shown next to organic search results on Google.com can significantly improve content discovery for users and advertisers, both large and small. Search ads on Google Play will enable developers to drive more awareness of their apps and provide consumers new ways to discover apps that they otherwise might have missed.

In the coming weeks, a limited set of users will begin to see ads from a pilot group of advertisers who are already running Google search ads for their apps. We’ll have more to share in the coming months about the expansion of this program as we look at the results and feedback. We believe search ads will be a useful addition to Google Play for users and developers alike, and we hope this will bring even more success to our developer community.

Categories: Programming

Bringing apps to the workplace with Google Play for Work

Thu, 02/26/2015 - 00:17

Posted by Matt Goodridge, Google Play team

Work doesn’t just happen in an office from 9 to 5 anymore. Today’s workers are mobile workers, and they need to be able to get things done as efficiently and collaboratively as possible, at any time. That’s why the Android for Work initiative is bringing together partners across the ecosystem, from device and app makers to networking and management solutions, to provide businesses with a secure, flexible and reliable mobility platform that users already know and love.

Google Play for Work allows businesses to securely deploy and manage enterprise-grade apps, across all of their users running Android for Work. Google Play for Work simplifies the process of distributing apps to employees and ensures that IT approves every deployed app. For developers, this is an opportunity to reach a new audience at scale through bulk installs or purchasing, which enables easy installation of your app across enterprises.

How to join Google Play for Work

Free apps will be available on Google Play for Work at launch with no action needed on your part. If you have a paid app, you’ll soon be able to opt-in to make your app available for bulk purchase on Google Play for Work in the Developer Console during the app publishing process. Find out more about publishing in the Google Play Developer Help Center.

Designing great apps for Android for Work

Apps that are installed from Google Play for Work will function without code changes. However, please note that some of the controls that Android for Work offers IT admins could affect how your app works. To ensure the best possible experience for your users, watch the first in our series of Android for Work DevBytes below to understand the best practices you should be following in developing your app.

More DevBytes will be posted to our YouTube channel soon. Find out more about Android for Work.

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Categories: Programming

We'll see you at GDC 2015!

Tue, 02/24/2015 - 21:05

Posted by Greg Hartrell, Senior Product Manager of Google Play Games

The Game Developers Conference (GDC) is less than one week away in San Francisco. This year we will host our annual Developer Day at West Hall and be on the Expo floor in booth #502. We’re excited to give you a glimpse into how we are helping mobile game developers build successful businesses and improve user experiences.

Our Developer Day will take place in Room 2006 of the West Hall of Moscone Center on Monday, March 2. We're keeping the content action-oriented with a few presentations and lightning talks, followed by a full afternoon of hands on hacking with Google engineers. Here’s a look at the schedule:

Opening Keynote || 10AM: We’ll kick off the day by sharing to make your games more successful with Google. You’ll hear about new platforms, new tools to make development easier, and ways to measure your mobile games and monetize them.

Running A Successful Games Business with Google || 10:30AM: Next we’ll hear from Bob Meese, the Global Head of Games Business Development from Google Play, who’ll offer some key pointers on how to make sure you're best taking advantage of unique tools on Google Play to grow your business effectively.

Lightning Talks || 11:15AM: Ready to absorb all the opportunities Google has to offer your game business? These quick, 5-minute talks will cover everything from FlatBuffers to Google Cast to data interpolation. To keep us on track, a gong may be involved.

Code Labs || 1:30PM: After lunch, we’ll turn the room into a classroom setting where you can participate in a number of self-guided code labs focused on leveraging Analytics, Google Play game services, Firebase and VR with Cardboard. These Code Labs are completely self-paced and will be available throughout the afternoon. If you want admission to the code labs earlier, sign up for Priority Access here!

Also, be sure to check out the Google booth on the Expo floor to get hands on experiences with Project Tango, Niantic Labs and Cardboard starting on Wednesday, March 4. Our teams from AdMob, AdWords, Analytics, Cloud Platform and Firebase will also be available to answer any of your product questions.

For more information on our presence at GDC, including a full list of our talks and speaker details, please visit g.co/dev/gdc2015. Please note that these events are part of the official Game Developer's Conference, so you will need a pass to attend. If you can't attend GDC in person, you can still check out our morning talks on our livestream at g.co/dev/gdc-livestream.

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Categories: Programming

Android Developer Story: GinLemon - Breaking through with Google Play

Tue, 02/24/2015 - 19:11

Posted by Letitia Lago, Google Play team

It’s not often that a developer is born from a summer holiday joke and a parent’s love of furniture making. But this is exactly how Vincenzo Colucci started GinLemon, a successful app business on Google Play.

The choice of Android was an obvious one to Vincenzo, although he didn’t have experience with Android development at the start — he learned it by downloading the tools and playing with the examples.

From his original scratch card app, to the global success of Smart Launcher, Vincenzo is proof that great apps can come from personal passion and the willingness to do something a little different.

Find out more about Vincenzo’s journey in this video.

Vincenzo and the team he has built around Smart Launcher are working on a major update, which will be free and they hope to release in March. They also have Smart Locker, a series of lock screens with some unique features, in development and other projects in the pipeline.

To learn about creating apps for Google Play and building your own app business, check out The Secrets to App Success on Google Play [ebook], a detailed playbook on the best practices and tools you can use to maximize the reach, retention, and revenue of your new app.

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Categories: Programming

Building for Android Wear: Depth and Flexibility

Wed, 02/18/2015 - 22:07

Posted by Timothy Jordan, Developer Advocate

With so many recent updates and improvements to Android Wear, it's high time to share an updated overview of the platform. We're certainly not done—there's a lot more to come—but this is the picture today as you start or continue developing your groundbreaking Android Wear user experiences.

Guns'n'Glory Heros and Strava

The Android Wear platform emphasizes depth and flexibility. Built on Android, it allows developers to use familiar APIs to create useful, performant, and imaginative apps that run directly on the watch. In the spirit of Android, you have the freedom to make substantial changes to the user experience, including the creation of custom watch faces. There are three main categories of experiences you can build: apps, custom watch faces, and notifications.

Apps

Apps that are built for Android Wear run directly on the watch and can do nearly anything a phone can, from tracking your run to giving you a little entertainment while waiting for the bus. Some even work without a connection to the phone, such as fitness and music apps. There are libraries to help you move data between the phone and the wearable, as well as create stunning and adaptable UIs. Here's a list of some of the great features you have access to:

table, th, td { border: 1px solid black; border-collapse: collapse; } td { padding: 5px; } Feature Documentation Full screen activities with touch events Creating Custom UIs for Wear Devices Notifications and custom actions UI Patterns for Android Wear Custom Watch faces Creating Watch Faces Layouts for round and square devices Creating Custom UIs for Wear Devices OpenGL Displaying Graphics with OpenGL ES Sensors
  • Accelerometer
  • Gyroscope
  • Compass
  • Barometer
  • Heart rate sensor
SensorManager Haptics Vibrator Microphone AudioRecord Voice actions Adding Voice Capabilities GPS Detecting Location on Android Wear Offline storing of data / music Transferring Assets Media playback controls MediaSession, MediaController Framework based on Android 5.0 API 21 Android 5.0 APIs Standalone or synchronized apps Sending and Syncing Data

Selected watch faces

Watch Faces

The ability to create custom watch faces gives you direct access to the most prominent UI element on a user's most personal device. The API is simple enough to build watch faces quickly and flexible enough to allow personalization. Again, given the depth and flexibility of the Android platform, you can create something for the user that's both beautiful and packed with unique features.

The development journey starts with the simplicity of bringing your design to the wrist. At the core of the watch face API is the onDraw method that allows you to draw whatever design you can think of to the canvas at a high enough frame rate to deliver fluid animation. This will come through at full fidelity while the watch is in interactive mode.

At other times, when the watch is in ambient mode, you're able to draw a more discreet version of the watch face. Additional preferences can be set to arrange the system UI elements appropriately for your design. Once those basics are covered, the limits are your imagination! You can go further with additions like the moon phase, current weather, or fitness stats. Watchmakers call these items "complications" -- but with Android they're hardly complicated. Once you have the data, just draw it on the canvas as you did the time.

Glympse and WhatsApp

Notifications

Of course, Android Wear Notifications are the easiest way to get started in the world of wearables. If you've got an Android app with notifications -- they already work on a Wear watch. If you've already enhanced your notification with actions, this is even better and also automatically already works. You can take things further with Wear-specific functionality like Stacks, Pages, and Voice Replies that make your notifications richer experiences on the wrist.

The user experiences you build for Wear get to take advantage of the power and flexibility of the Android platform. It's easy to get started and possible to create truly groundbreaking UI for your users. Together, we can create an ecosystem of user experiences as diverse as the watches they run on and the people who wear them.

Check out the developer videos and documentation for more, and share your thoughts on the Android Wear Developers community. We can’t wait to see the innovative user experiences you will build on Android Wear.

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Categories: Programming

Beta Channel for the Android WebView

Fri, 02/13/2015 - 16:59

Posted by Richard Coles, Software Engineer, Google London

Many Android apps use a WebView for displaying HTML content. In Android 5.0 Lollipop, Google has the ability to update WebView independently of the Android platform. Beginning today, developers can use a new beta channel to test the latest version of WebView and provide feedback.

WebView updates bring numerous bug fixes, new web platform APIs and updates from Chromium. If you’re making use of the WebView in your app, becoming a beta channel tester will give you an early start with new APIs as well as the chance to test your app before the WebView rolls out to your users.

The first version offered in the beta channel will be based on Chrome 40 and you can find a full list of changes on the chromium blog entry.

To become a beta tester, join the community which will enable you to sign up for the Beta program; you’ll then be able to install the beta version of the WebView via the Play Store. If you find any bugs, please file them on the Chromium issue tracker.

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Categories: Programming

Trulia sees 30% more engagement using notifications and further innovates with Android Wear

Wed, 02/11/2015 - 20:01

Posted by Laura Della Torre, Google Play team

Trulia’s mission is to make it as easy as possible for home buyers, sellers, owners and renters to navigate the real estate market. Originally a website-based company, Trulia is keenly aware that its users are migrating to mobile. Today, more than 50 percent of Trulia’s business comes from mobile and growth shows no sign of slowing, so they know that’s where they need to innovate.

In the following video, Jonathan McNulty, VP of Consumer Product, and Lauren Hirashima, Mobile Product Manager, at Trulia, talked about how the company successfully leveraged notifications on Android to increase app engagement by 30 percent and has seen 2x the amount of engagement on Android relative to other platforms:

Trulia continues to focus on improving their mobile experience, using Google’s geo-fencing technology to create Nearby Home Alerts, which lets users know when they walk near a new listing. Combined with Android Wear, Trulia now makes it possible for users to see details and photos about a property and call or email the agent, all directly from their watch.

Find out more about using rich notifications on Android and developing for Android Wear. And check out The Secrets to App Success on Google Play (ebook) which contains a chapter dedicated to the best practices and tools you can use to increase user engagement and retention in your app.

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Categories: Programming

The Guardian — Understanding and engaging mobile users

Wed, 02/11/2015 - 20:00

Posted by Leticia Lago, Google Play team

The Guardian is a global news organization with one of the world's largest quality English-speaking news websites, theguardian.com. It has more than 100 million monthly unique browsers and app users, two thirds of which come from outside the UK. With a longstanding reputation for agenda-setting journalism, the publication is most recently renowned for its Pulitzer Prize and Emmy-winning coverage of the disclosures made by whistleblower Edward Snowden. The Guardian’s early adoption of a digital-first policy and continued digital innovation means it has also become a respected name among developers and tech audiences. In the last year, it has launched a redesigned app and new website and been among a handful of publishers to develop its own Glassware.

The Guardian app is taking advantage of unique Google Play and Android features to drive user engagement. Their mobile app readers are now 10 to 20 times more engaged than their average web users. Improving engagement has also helped them lift the rating for their app from 4.0 to 4.4 on Google Play.

Anthony Sullivan, Director of Product, and Tom Grinsted, Product Manager, share some best practices for increasing app engagement in this video.

To learn more, be sure to check out these resources to better engage your users:

  • Convert installs to active users [video] — hear from Matteo Vallone, Partner Development Manager for Google Play, about the best practices for engaging and retaining users through intents, identity, context, and rich notifications as well as delivering a cross-platform user experience.
  • Adding Wearable Features to Notifications [tutorial] — learn how to add notifications to Android Wear devices, including how to make use of the Wear notification features: voice commands, stacks, and pages.
  • Beta testing [help] — discover how to make use of the alpha and beta testing features offered by Google Play, and get feedback from real users.
  • Build your community (of testers) [guide] — get advice on how to build communities on G+ or other social networks, then tap into their skills and enthusiasm to help with testing your app.
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Categories: Programming

Android Wear & QR Code: Putting Users through the Fast Track

Tue, 01/27/2015 - 13:18

Posted by Hoi Lam, Developer Advocate

Rushing onto a train, entering a concert, or simply ordering a coffee, we have all seen users (or ourselves) rummaging through their wallets or mobile app trying to get the right boarding pass, ticket or loyalty card. With Android Wear and a few lines of code in your mobile app, this can all work like magic.

What’s new in the Android Support Library

While QR Code images could be attached to a notification since the first release of the Android Wear platform, developers have asked about two situations which they would like to see improve:

  1. With circular displays, it is hard for developer to know if the QR code is displayed in it’s entirety and not cropped.
  2. To conserve battery, Android Wear switches off the screen after five seconds of inactivity. However, this makes it hard for the user to ensure that the QR code is still displayed on their wrist when they reach the front of the queue.

With the latest support library, we have added two additional methods to WearableExtender to give developers more control over how background images are displayed in notifications. These new APIs can be used in a number of scenarios, we will focus on the QR code use case in this post:

  • Ensure the image is not cropped - setHintAvoidBackgroundClipping(true)
  • With this new method, developers can ensure that the entire QR code is always visible. table, th, td { border: 1px solid black; border-collapse: collapse; } Wrong:
    setHintAvoidBackgroundClipping (false)
    // this is the Default Right:
    setHintAvoidBackgroundClipping (true)
  • Ensure the QR code is still displayed when the user gets to the front of the queue - setHintScreenTimeout(timeInMS)
  • This new method enables developers to set a timeout that makes sense for their specific use case.
Design Best Practices

We have experimented with a number of customization options with QR codes and here are some of the lessons learnt:

Dos
  • Do test with your equipment - Before deploying, test with your QR code readers to ensure that the QR code displayed on the wearable works with your equipment.
  • Do use black and white QR codes - This ensures maximum contrasts and makes it easier for the reader to read the information.
  • Do display only the core information in the text notification - Remember that less is more. Glanceability is important for wearables.
  • Do test with both round and square watches - The amount of text can be displayed on the notification varies especially dependent on the form factor (square and circular).
  • Do brand with icon - On the main notification in the Android Wear stream, developers can set a full color icon using setLargeIcon to brand your notification.
  • Do convey additional information using background - To achieve an even better result, consider setting context sensitive backgrounds through setBackground, such as a photo of the destination for the train or a picture of the stadium.
  • Do use QR codes which are 400x400 pixels or larger - In line with other background images, the recommended minimum size for QR code is 400x400 pixels.
Don'ts
  • Do not brand the QR code - The screen real estate is limited on Android Wear and using some of this for branding may result in the QR code not working correctly.
  • Do not use anything other than grey or default theme color for notification text - Although Android Wear notifications support basic text formatting such as setting text color, this should be used in moderation with the color set to default or grey. The reason is that the Holo theme for Android 4.x has a default background of black whereas Material Design theme for Android 5+ including Android Wear has a white background. This makes it hard for the colour to work for both themes. Bold and Italic are fine formatting choices.
Android Wear is for people on the move

Using QR codes on Android Wear is a very delightful experience. The information that the user needs is right on their wrist at the right time in the right place. With the new APIs, you can now unlock more doors than ever before and give users an easier time with check in on the go.

Sample code can be downloaded from this repository.

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Categories: Programming

How Google Analytics helps you make better decisions for your apps

Fri, 01/16/2015 - 01:12

Posted by Russell Ketchum, Lead Product Manager, Google Analytics for Mobile Apps

Knowing how your customers use your app is the foundation to keeping them happy and engaged. It’s important to track downloads and user ratings, but the key to building a successful business is using data to dive deeper into understanding the full acquisition funnel and what makes users stick around.

Google Analytics is the easiest way to understand more about what your users are doing inside your app on Google Play, while also simultaneously tracking your users across the web and other mobile platforms. To show how Google Analytics can help, we've created a new "Analyze" section on the Android Developers website for you to check out. We provide guidance on how to design a measurement plan and implement effective in-app analytics – and take advantage of features only available between Google Play and Google Analytics.

The Google Play Referral Flow in Analytics

Google Analytics for mobile apps provides a comprehensive view into your app’s full user lifecycle, including user acquisition, composition, in app behavior, and key conversions. Our Analytics Academy course on mobile app analytics is also a great resource to learn the fundamentals.

Eltsoft LLC, a foreign language learning and education app developer for Android, recognized early on how impactful Google Analytics would have on the company's ability to quickly improve on its apps and meet user needs.

Analytics has really helped us to track the effectiveness of the changes to our app. I would say six months ago, that our success was a mystery. The data said we were doing well, but the whys were not clear. Therefore, we couldn’t replicate or push forward. But today, we understand what’s happening and can project our future success. We have not only the data, but can control certain variables allowing us to understand that data. - Jason Byrne, Eltsoft LLC

Here are some powerful tips to make the most of Google Analytics:

  1. Understand the full acquisition funnel
  2. Uniquely integrated with the Google Play Developer Console, Google Analytics gives you a comprehensive view of the Google Play Referral Flow. By linking Analytics to the Developer Console, you can track useful data on how users move through the acquisition flow from your marketing efforts to the Google Play store listing to the action of launching the app. If you find that a significant number of users browse your app in Google Play, but don’t install it, for example, you can then focus your efforts on improving your store listing.
  3. Unlock powerful insights on in-app purchases
  4. Monitoring in-app purchases in the Google Play Developer Console will show you the total revenue your app is generating, but it does not give you the full picture about your paying users. By instrumenting your app with the Google Analytics ecommerce tracking, you’ll get a fuller understanding of what paying users do inside your app. For example, you can find out which acquisition channels deliver users who stay engaged and go on to become the highest value users.
  5. Identify roadblocks and common paths with the Behavior Flow
  6. Understanding how users move through your app is best done with in-app analytics. With Google Analytics, you can easily spot if a significant percentage of users leave your app during a specific section. For example, if you see significant drop off on a certain level of your game, you may want to make that level easier, so that more users complete the level and progress through the game. Similarly, if you find users who complete a tutorial stay engaged with your app, you might put the tutorial front and center for first-time users.
  7. Segment your audience to find valuable insights
  8. Aggregated data can help you answer questions about overall trends in your app. If you want to unlock deeper insights about what drives your users’ behavior, you can slice and dice your data using segmentation, such as demographics, behavior, or install date. If something changes in one of your key metrics, segmentation can help you get to the root of the issue -- for example, was a recent app update unpopular with users from one geographic area, or were users with a certain device or carrier affected by a bug?
  9. Use custom data to measure what matters for your business
  10. Simply activating the Google Analytics library gives you many out-of-the-box metrics without additional work, such as daily and monthly active users, session duration, breakdowns by country, and many more variables. However, it’s likely that your app has many user actions or data types that are unique to it, which are critical to building an engaged user base. Google Analytics provides events, custom dimensions, and custom metrics so you can craft a measurement strategy that fits your app and business.
  11. No more one-size-fits-all ad strategy
  12. If you’re a developer using AdMob to monetize your app, you can now see all of your Analytics data in the AdMob dashboard. Running a successful app business is all about reaching the right user with the right ad or product at the right time. If you create specific user segments in Google Analytics, you can target each segment with different ad products. For example, try targeting past purchasers with in-app purchase ads, while monetizing users who don’t purchase through targeted advertising.

By measuring your app performance on a granular level, you will be able to make better decisions for your business. Successful developers build their measurement plan at the same time as building their app in order to set goals and track progress against key success metrics, but it’s never too late to start.

Choose the implementation that works best for your app to get started with Google Analytics today and find out more about what you can do in the new “Analyze” section of developers.android.com.

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Efficient Game Textures with Hardware Compression

Tue, 01/13/2015 - 20:43

Posted by Shanee Nishry, Developer Advocate

As you may know, high resolution textures contribute to better graphics and a more impressive game experience. Adaptive Scalable Texture Compression (ASTC) helps solve many of the challenges involved including reducing memory footprint and loading time and even increase performance and battery life.

If you have a lot of textures, you are probably already compressing them. Unfortunately, not all compression algorithms are made equal. PNG, JPG and other common formats are not GPU friendly. Some of the highest-quality algorithms today are proprietary and limited to certain GPUs. Until recently, the only broadly supported GPU accelerated formats were relatively primitive and produced poor results.

With the introduction of ASTC, a new compression technique invented by ARM and standardized by the Khronos group, we expect to see dramatic changes for the better. ASTC promises to be both high quality and broadly supported by future Android devices. But until devices with ASTC support become widely available, it’s important to understand the variety of legacy formats that exist today.

We will examine preferable compression formats which are supported on the GPU to help you reduce .apk size and loading times of your game.

Texture Compression

Popular compressed formats include PNG and JPG, which can’t be decoded directly by the GPU. As a consequence, they need to be decompressed before copying them to the GPU memory. Decompressing the textures takes time and leads to increased loading times.

A better option is to use hardware accelerated formats. These formats are lossy but have the advantage of being designed for the GPU.

This means they do not need to be decompressed before being copied and result in decreased loading times for the player and may even lead to increased performance due to hardware optimizations.

Hardware Accelerated Formats

Hardware accelerated formats have many benefits. As mentioned before, they help improve loading times and the runtime memory footprint.

Additionally, these formats help improve performance, battery life and reduce heating of the device, requiring less bandwidth while also consuming less energy.

There are two categories of hardware accelerated formats, standard and proprietary. This table shows the standard formats:

table { border-collapse: collapse; } table, th, td { border: 1px solid black; } td { padding: 5px; } ETC1 Supported on all Android devices with OpenGL ES 2.0 and above. Does not support alpha channel. ETC2 Requires OpenGL ES 3.0 and above. ASTC Higher quality than ETC1 and ETC2. Supported with the Android Extension Pack.

As you can see, with higher OpenGL support you gain access to better formats. There are proprietary formats to replace ETC1, delivering higher quality and alpha channel support. These are shown in the following table:

table { border-collapse: collapse; } table, th, td { border: 1px solid black; }td { padding: 5px; } ATC Available with Adreno GPU. PVRTC Available with a PowerVR GPU. DXT1 S3 DXT1 texture compression. Supported on devices running Nvidia Tegra platform. S3TC S3 texture compression, nonspecific to DXT variant. Supported on devices running Nvidia Tegra platform.

That’s a lot of formats, revealing a different problem. How do you choose which format to use?

To best support all devices you need to create multiple apks using different texture formats. The Google Play developer console allows you to add multiple apks and will deliver the right one to the user based on their device. For more information check this page.

When a device only supports OpenGL ES 2.0 it is recommended to use a proprietary format to get the best results possible, this means making an apk for each hardware.

On devices with access to OpenGL ES 3.0 you can use ETC2. The GL_COMPRESSED_RGBA8_ETC2_EAC format is an improved version of ETC1 with added alpha support.

The best case is when the device supports the Android Extension Pack. Then you should use the ASTC format which has better quality and is more efficient than the other formats.

Adaptive Scalable Texture Compression (ASTC)

The Android Extension Pack has ASTC as a standard format, removing the need to have different formats for different devices.

In addition to being supported on modern hardware, ASTC also offers improved quality over other GPU formats by having full alpha support and better quality preservation.

ASTC is a block based texture compression algorithm developed by ARM. It offers multiple block footprints and bitrate options to lower the size of the final texture. The higher the block footprint, the smaller the final file but possibly more quality loss.

Note that some images compress better than others. Images with similar neighboring pixels tend to have better quality compared to images with vastly different neighboring pixels.

Let’s examine a texture to better understand ASTC:

This bitmap is 1.1MB uncompressed and 299KB when compressed as PNG.

Compressing the Android jellybean jar texture into ASTC through the Mali GPU Texture Compression Tool yields the following results.

table { border-collapse: collapse; } table, th, td { border: 1px solid black; }td { padding: 5px; } Block Footprint 4x4 6x6 8x8 Memory 262KB 119KB 70KB Image Output Difference Map 5x Enhanced Difference Map

As you can see, the highest quality (4x4) bitrate for ASTC already gains over PNG in memory size. Unlike PNG, this gain stays even after copying the image to the GPU.

The tradeoff comes in the detail, so it is important to carefully examine textures when compressing them to see how much compression is acceptable.

Conclusion

Using hardware accelerated textures in your games will help you reduce the size of your .apk, runtime memory use as well as loading times.

Improve performance on a wider range of devices by uploading multiple apks with different GPU texture formats and declaring the texture type in the AndroidManifest.xml.

If you are aiming for high end devices, make sure to use ASTC which is included in the Android Extension Pack.

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Making a performant watch face

Tue, 12/23/2014 - 19:42

Posted by Hoi Lam, Developer Advocate, Android Wear

What’s a better holiday gift than great performance? You’ve got a great watch face idea -- now, you want to make sure the face you’re presenting to the world is one of care and attention to detail.

At the core of the watch face's process is an onDraw method for canvas operations. This allows maximum flexibility for your design, but also comes with a few performance caveats. In this blog post, we will mainly focus on performance using the real life journey of how we optimised the Santa Tracker watch face, more than doubling the number of fps (from 18 fps to 42 fps) and making the animation sub-pixel smooth.

Starting point - 18 fps

Our Santa watch face contains a number of overlapping bitmaps that are used to achieve our final image. Here's a list of them from bottom to top:

  1. Background (static)
  2. Clouds which move to the middle
  3. Tick marks (static)
  4. Santa figure and sledge (static)
  5. Santa’s hands - hours and minutes
  6. Santa’s head (static)

The journey begins with these images...

Large images kill performance (+14 fps)

Image size is critical to performance in a Wear application, especially if the images will be scaled and rotated. Wasted pixel space (like Santa’s arm here) is a common asset mistake:

Before: 584 x 584 = 341,056 pixelsAfter: 48*226 = 10,848 (97% reduction)

It's tempting to use bitmaps from the original mock up that have the exact location of watch arms and components in absolute space. Sadly, this creates problems, like in Santa's arm here. While the arm is in the correct position, even transparent pixels increase the size of the image, which can cause performance problems due to memory fetch. You'll want to work with your design team to extract padding and rotational information from the images, and rely on the system to apply the transformations on our behalf.

Since the original image covers the entire screen, even though the bitmap is mostly transparent, the system still needs to check every pixel to see if they have been impacted. Cutting down the area results in significant gains in performance. After correcting both of the arms, the Santa watch face frame rate increased by 10 fps to 28 fps (fps up 56%). We saved another 4 fps (fps up 22%) by cropping Santa’s face and figure layer. 14 fps gained, not bad!

Combine Bitmaps (+7 fps)

Although it would be ideal to have the watch tick marks on top of our clouds, it actually does not make much difference visually as the clouds themselves are transparent. Therefore there is an opportunity to combine the background with the ticks.

+

When we combined these two views together, it meant that the watch needed to spend less time doing alpha blending operations between them, saving precious CPU time. So, consider collapsing alpha blended resources wherever we can in order to increase performance. By combining two full screen bitmaps, we were able to gain another 7 fps (fps up 39%).

Anti-alias vs FilterBitmap flags - what should you use? (+2 fps)

Android Wear watches come in all shapes and sizes. As a result, it is sometimes necessary to resize a bitmap before drawing on the screen. However, it is not always clear what options developers should select to make sure that the bitmap comes out smoothly. With canvas.drawBitmap, developers need to feed in a Paint object. There are two important options to set - they are anti-alias and FilterBitmap. Here’s our advice:

  • Anti-alias does not do anything for bitmaps with transparent edges. We often switch on the anti-alias option by default as developers when we are creating a Paint object. However, this option only really makes sense for vector objects. For bitmaps, this is used to blend the rectangular edges if it is rotated or skewed and it has no impact if the edge pixels are transparent (as we would imagine most watch face arms would be). The hand on the left below has anti-alias switched on, the one on the right has it switched off. So turn off anti-aliasing for bitmaps to gain performance back. For our watch face, we gained another 2 fps (fps up 11%) by switching this option off.
  • Switch on FilterBitmap for all bitmap objects which are on top of other objects - this option smooths the edges when drawBitmap is called. This should not be confused with the filter option on Bitmap.createScaledBitmap for resizing bitmaps. We need both to be turned on. The bitmaps below are the magnified view of Santa’s hand. The one on the left has FilterBitmap switched off and the one on the right has FilterBitmap switched on.
Eliminate expensive calls in the onDraw loop (+3 fps)

onDraw is the most critical function call in watch faces. It's called for every drawable frame, and the actual painting process cannot move forward until it's finished. As such, our onDraw method should be as light and as performant as possible. Here's some common problems that developers run into that can be avoided:

  1. Do move heavy and common code to a precompute function - e.g. if we commonly grab R.array.cloudDegrees, try doing that in onCreate, and just referencing it in the onDraw loop.
  2. Don’t repeat the same image transform in onDraw - it’s common to resize bitmaps at runtime to fit the screen size but this is not available in onCreate. To avoid resizing the bitmap over and over again in onDraw, override onSurfaceChanged where width and height information are available and resize images there.
  3. Don't allocate objects in onDraw - this leads to high memory churn which will force garbage collection events to kick off, killing frame rates.
  4. Do analyze the CPU performance by using a tool such as the Android Device Monitor. It’s important that the onDraw execution time is short and occurs in a regular period.

Following these simple rules will improve rendering performance drastically.

In the first version, the Santa onDraw routine has a rogue line:

int[] cloudDegrees = 
    getResources().getIntArray(R.array.cloudDegrees);

This loads the int array on every call from resources which is expensive. By eliminating this, we gained another 3 fps (fps up 17%).

Sub-pixel smooth animation (-2 fps)

For those keeping count, we should be 44 fps, so why is the end product 42 fps? The reason is a limitation with canvas.drawBitmap. Although this command takes left and top positioning settings as a float, the API actually only deals with integers if it is purely translational for backwards compatibility reasons. As a result, the cloud can only move in increments of a whole pixel resulting in janky animations. In order to be sub-pixel smooth, we actually need to draw and then rotate rather than having pre-rotate clouds which moves towards Santa. This additional rotation costs us 2 fps. However, the effect is worthwhile as the animation is now sub-pixel smooth.

Before - fast but janky and wobbly

for (int i = 0; i < mCloudBitmaps.length; i++) {
    float r = centerX - (timeElapsed / mCloudSpeeds[i]) % centerX;
    float x = centerX + 
        -1 * (r * (float) Math.cos(Math.toRadians(cloudDegrees[i] + 90)));
    float y = centerY - 
        r * (float) Math.sin(Math.toRadians(cloudDegrees[i] + 90));
    mCloudFilterPaints[i].setAlpha((int) (r/centerX * 255));
    Bitmap cloud = mCloudBitmaps[i];
    canvas.drawBitmap(cloud,
        x - cloud.getWidth() / 2,
        y - cloud.getHeight() / 2,
        mCloudFilterPaints[i]);
}

After - slightly slower but sub-pixel smooth

for (int i = 0; i < mCloudBitmaps.length; i++) {
    canvas.save();
    canvas.rotate(mCloudDegrees[i], centerX, centerY);
    float r = centerX - (timeElapsed / (mCloudSpeeds[i])) % centerX;
    mCloudFilterPaints[i].setAlpha((int) (r / centerX * 255));
    canvas.drawBitmap(mCloudBitmaps[i], centerX, centerY - r,
        mCloudFilterPaints[i]);
    canvas.restore();
}

Before: Integer translation values create janky, wobbly animation. After: smooth sailing!

Quality on every wrist

The watch face is the most prominent UI element in Android Wear. As craftspeople, it is our responsibility to make it shine. Let’s put quality on every wrist!

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Build Mobile App Services with Google Cloud Tools for Android Studio v1.0

Fri, 12/19/2014 - 22:56

Posted by Chris Sells, Product Manager, Cloud Tools for Android Studio

Cloud Tools for Android Studio allows you to simultaneously build the service- and client-side of your mobile app. Earlier this month, we announced the release of Android Studio 1.0 that showed just how much raw functionality there is available for Android app developers. However, the client isn’t the whole picture, as most mobile apps also need one or more web services. It was for this reason that the Cloud Tools for Android Studio were created.

Cloud Tools put the power of Google App Engine in the same IDE alongside of your mobile client, giving you all the same Java language tools for both sides of your app, as well as making it far easier for you to keep them in sync as each of them changes.

Getting Started

To get started with Cloud Tools for Android Studio, add a New Module to your Android Studio project, choose Google Cloud Module and you’ll have three choices:

You can add three Google Cloud module types to your Android Studio project

The Java Servlet Module gives you a plain servlet class for you to implement as you see fit. If you’d like help building your REST endpoints with declarative routing and HTTP verbs and automatic Java object serialization to and from JSON, then you’ll want the Java Endpoints Module. If you want the power of endpoints, along with the ability to send notifications from your server to your clients, then choose Backend with Google Cloud Messaging.

Once you’re done, you’ll have your service code right next to your client code:

You can build your mobile app’s client and service code together in a single project

Not only does this make it very convenient to build and test your entire end-to-end, but we also dropped a little extra something into your app’s build.gradle file:

The android-endpoints configuration build step in your build.gradle file creates a client-side library for your server-side endpoint

The updated Gradle file will now create a library for use in your app’s client code that changes when your service API changes. This library lets you call into your service from your client and provides full code completion as you do:

The client-side endpoint library provides code completion and documentation

Instead of writing the code to create HTTP requests by hand, you can make calls via the library in a typesafe manner and the marshalling from JSON to Java will be handled for you, just like on the server-side (but in reverse, of course).

Endpoints Error Detection

Meanwhile, back on the server-side, as you make changes to your endpoints, we’re watching to make sure that they’re in good working order even before you compile by checking the attributes as you type:

Cloud Tools will detect errors in your endpoint attributes

Here, Cloud Tools have found a duplicate name in the ApiMethod attribute, which is easy to do if you’re creating a new method from an existing method.

Creating an Endpoint from an Objectify Entity

If, as part of your endpoint implementation, you decide to take advantage of the popular Objectify library, you’ll find that Cloud Tools provides special support for you. When you right-click (or control-click on the Mac) on a file containing an Objectify entity class, you’ll get the Generate Cloud Endpoint from Java class option:

The generate Cloud Endpoint from Java class option will create a CRUD endpoint for you

If you’re running this option on a Java class that isn’t built with Objectify, then you’re going to get an endpoint with empty methods for get and insert operations that you can implement as appropriate. However, if you do this with an Objectify entity, you’ll get a fully implemented endpoint:

Cloud Tools has built-in support for generating Objectify-based cloud endpoint implementations

Using your Cloud Endpoint

As an Android developer, you’re used to deploying your client first in the emulator and then into a local device. Likewise, with the service, you’ll want to test first to your local machine and then, when you’re ready, deploy into a Google App Engine project. You can run your service app locally by simply choosing it from the Configurations menu dropdown on the toolbar and pressing the Run button:

The Configurations menu in the toolbar lets you launch your service for testing

This will build and execute your service on http://localhost:8080/ (by default) so that you can test against it with your Android app running in the emulator. Once you’re ready to deploy to Google Cloud Platform, you can do so by selecting the Deploy Module to App Engine option from the Build menu, where you’ll be able to choose the source module you want to deploy, log into your Google account and pick the target project to which you’d like to deploy:

The Deploy to App Engine dialog will use your Google credentials to enumerate your projects for you

Cloud Tools beta required some extra copying and pasting to get the Google login to work, but all of that’s gone now in this release.

What’s Next?

We’re excited to get this release into your hands, so if you’ve haven’t downloaded it yet, then go download Android Studio 1.0 right now! To take advantage of Cloud Tools for Android Studio, you’ll want to sign up for a free Google Cloud Platform trial. Nothing is stopping you from building great Android apps from front to back. If you’ve got suggestions, drop us a line so that we can keep improving. We’re just getting started putting Google Cloud Platform tools in your hands. We can’t wait to see what you’ll build.

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Google Play game services ends year with a bang!

Fri, 12/19/2014 - 20:31

Posted by Benjamin Frenkel, Product Manager, Play Games

In an effort to supercharge our Google Play games services (GPGS) developer tools, we’re introducing the Game services Publishing API, a revamped Unity Plugin, additional enhancements to the C++ SDK, and improved Leaderboard Tamper Protection.

Let’s dig into what’s new for developers:

Publishing API to automate game services configuration

At Google I/O this past June, the pubsite team launched the Google Play Developer Publishing APIs to automate the configuration and publishing of applications to the Play store. Game developers can now also use the Google Play game services Publishing API to automate the configuration and publishing of game services resources, starting with achievements and leaderboards.

For example, if you plan on publishing your game in multiple languages, the game services Publishing API will enable you to pull translation data from spreadsheets, CSVs, or a Content Management System (CMS) and automatically apply those translations to your achievements.

Early adopter Square Enix believes the game services Publishing API will be an indispensable tool to manage global game rollouts:


Achievements are the most used feature in Google Play game services for us. As our games support more languages, achievement management has become increasingly difficult. With the game services Publishing API, we can automate this process, which is really helpful. The game services Publishing API also comes with great samples that we were able to easily customize for our needs

Keisuke Hata, Manager / Technical Director, SQUARE ENIX Co., Ltd.





To get started today, take a look at the developer documentation here.

Updated Unity plugin and Cross-platform C++ SDK
  • Unity plugin Saved Games support: You can now take advantage of the Saved Games feature directly from the Unity plugin, with more storage and greater discoverability through the Play Games app
  • New Unity plugin architecture: We’ve rewritten the plugin on top of our cross-platform C++ SDK to speed up feature development across SDKs and increase our responsiveness to your feedback
  • Improved Unity generated Xcode project setup: You now have a much more robust way to generate Xcode projects integrated with Google Play Game Services in Unity
  • Updated and improved Unity samples: We’ve updated our sample codes to make it easier for first time developers to integrate Google Play games services
  • C++ SDK support for iPhone 6 Plus: You can now take advantage of the out-of-box games services UI (e.g., for leaderboards and achievements) for larger form factor devices, such as the iPhone 6 Plus

We also include some important bug fixes and stability improvements. Check out the release notes for the Unity Plugin and the getting started page for the C++ SDK for more details.

Leaderboard Tamper Protection

Turn on Leaderboard Tamper Protection to automatically hide suspected tampered scores from your leaderboards. To enable tamper protection on an existing leaderboard, go to your leaderboard in the Play developer console and flip the “Leaderboard tamper protection” toggle to on. Tamper protection will be on by default for new leaderboards.Learn more.

To learn more about cleaning up previously submitted suspicious scores refer to the Google Play game services Management APIs documentation or get the web demo console for the Management API directly from github here.

In addition, if you prefer command-line tools, you can use the python-based option here. Join the discussion on

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New Code Samples for Lollipop

Thu, 12/11/2014 - 23:43

Posted by Trevor Johns, Developer Programs Engineer

With the launch of Android 5.0 Lollipop, we’ve added more than 20 new code samples demonstrating how to implement some of the great new features of this release. To access the code samples, you can easily import them in Android Studio 1.0 using the new Samples Wizard.

Go to File > Import Sample in order to browse the available samples, which include a description and preview for each. Once you’ve made your selection, select “Next” and a new project will be automatically created for you. Run the project on an emulator or device, and feel free to experiment with the code.

Samples Wizard in Android Studio 1.0 Newly imported sample project in Android Studio

Alternatively, you can browse through them via the Samples browser on the developer site. Each sample has an Overview description, Project page to browse app file structure, and Download link for obtaining a ZIP file of the sample. As a third option, code samples can also be accessed in the SDK Manager by downloading the SDK samples for Android 5.0 (API 21) and importing them as existing projects into your IDE.


Sample demonstrating transition animations
Material Design

When adopting material design, you can refer to our collection of sample code highlighting material elements:

For additional help, please refer to our design checklist, list of key APIs and widgets, and documentation guide.

To view some of these material design elements in action, check out the Google I/O app source code.

Platform

Lollipop brings the most extensive update to the Android platform yet. The Overview screen allows an app to surface multiple tasks as concurrent documents. You can include enhanced notifications with this sample code, which shows you how to use the lockscreen and heads-up notification APIs.

We also introduced a new Camera API to provide developers more advanced image capture and processing capabilities. These samples detail how to use the camera preview and take photos, how to record video, and implement a real-time high-dynamic range camera viewfinder.

Elsewhere, Project Volta encourages developers to make their apps more battery-efficient with new APIs and tools. The JobScheduler sample demonstrates how you can schedule background tasks to be completed later or under specific conditions.

For those interested in the enterprise device administration use case, there are sample apps on setting app restrictions and creating a managed profile.

Android Wear

For Android Wear, we have a speed tracker sample to show how to take advantage of GPS support on wearables. You can browse the rest of the Android Wear samples too, and here are some highlights that demonstrate the unique capabilities of wearables, such as data synchronization, notifications, and supporting round displays:

Android TV

Extend your app for Android TV using the Leanback library described in this training guide and sample.

To try out a game that is specifically optimized for Android TV, download Pie Noon from Google Play. It’s an open-source game developed in-house at Google that supports multiple players using Bluetooth controllers or touch controls on mobile devices.

Android Auto

For the use cases highlighted in the Introduction to Android Auto DevByte, we have two code samples. The Media Browser sample (DevByte) demonstrates how easy it is to make an audio app compatible with Android Auto by using the new Lollipop media APIs, while the Messaging sample (DevByte) demonstrates how to implement notifications that support replies using speech recognition.

Google Play services

Since we’ve discussed sample resources for the Android platform and form factors, we also want to mention that there are existing samples for Google Play services. With Google Play services, your app can take advantage of the latest Google-powered APIs such as Maps, Google Fit, Google Cast, and more. Access samples in the Google Play services SDK or visit the individual pages for each API on the developer site. For game developers, you can reference the Google Play Games services samples for how to add achievements, leaderboards, and multiplayer support to your game.

Check out a sample today to help you with your development!

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Hello World, meet our new experimental toolchain, Jack and Jill

Thu, 12/11/2014 - 20:22

Posted by Paul Rashidi, Developer Programs Engineer

We've been working on a new toolchain for Android that’s designed to improve build times and simplify development by reducing dependencies on other tools. Today, we’re introducing you to Jack (Java Android Compiler Kit) and Jill (Jack Intermediate Library Linker), the two tools at the core of the new toolchain.

We are making an early, experimental version of Jack and Jill available for testing with non-production versions of your apps. This post describes how the toolchain works, how to configure it, and how to let us know of your feature requests and any bugs you find.

So how does it work?

When the new tool chain is enabled, Jill will translate any libraries you are referencing to a new Jack library file (.jack). This prepares them to be quickly merged with other .jack files. The Android Gradle plugin and Jack collect any .jack library files, along with your source code, and compiles them into a set of dex files. During the process, Jack also handles any requested code minification. The output is then assembled into an APK file as normal. We also include support for multiple dex files, if you have enabled that support.

How do I use it?

Jack and Jill are already available in the 21.1.1+ Build Tools for Android Studio. Complementary Gradle support is also currently available in the Android 1.0.0+ Gradle plugin. To get started, all you need to do is make sure you're using these versions of the tooling and then add a single line in your build.gradle file. Perform a build of your application to receive a newly built APK.

android {
    ...
    buildToolsRevision '21.1.1'
    defaultConfig {
      // Enable the experimental Jack build tools.
      useJack = true
    }
    ...
}
If you want to build your app with both toolchains, Product Flavors are a great way to do this. Your build.gradle file might look something like the snippet below.
android {
    ...
    productFlavors {
        dev {
            ...
        }
        experimental {
            useJack = true
        }
        prod {
            ...
        }
    }
    ...
}
How do I configure my build?

We are making the transition to Jack as smooth as possible by supporting minification (shrinking and/or obfuscation), as well as repackaging (i.e. similar to tools like jarjar), while using the same input files as you are used to. Minification is available in the Gradle plugin immediately and repackaging will follow. You should continue to use the "minifyEnabled true" directive to reduce the size of your app among all other optimizations you would normally use. There are more details on our reference page (linked below) regarding the level of support for each type of optimization. We encourage you to provide feedback there if your current configuration isn't supported.

Give us your feedback

We are attempting to make the toolchain as easy to test out as possible and we're looking for your help to fine tune it. Use the reference page to find known issues, file feature requests, and report bugs. Happy building!

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Watch Face API Now Available for Android Wear

Thu, 12/11/2014 - 07:08

Posted by Wayne Piekarski, Developer Advocate

We’re pleased to announce that the official Android Wear Watch Face API is now available for developers. Watch faces give users even more ways to express their personal style, while creating an opportunity for developers to customize the most prominent UI feature of the watches. Watch faces have been the most requested feature from users and developers alike, and we can’t wait to see what you build for them.

An Introduction to Watch Faces for Android Wear by Timothy Jordan

Design and development

To get started, first learn about Designing Watch Faces, and then check out the Creating Watch Faces training class. The WatchFace Sample available online and in the Android Studio samples manager also provides a number of different examples to help you jump right in. For a quick overview, you can also watch the Watch Faces for Android Wear DevByte video above.

Watch faces are services that run from your wearable app, so you can provide one or multiple watch faces with a single app install. You can also choose to have configuration activities on the phone or watch, for example to let a user change between 12 and 24-hour time, or to change the watch face’s background. You can use OpenGL to provide smooth graphics, and a background service to pull in useful data like weather and calendar events. Watch faces can be analog, or digital, or display the time in some new way that hasn’t been invented yet––it’s up to you.

Updates to existing devices

Over the next week, the latest release of Android Wear, based on Android 5.0 and implementing API 21, will roll out to users. All Android Wear devices will be updated to Android 5.0 via an over-the air (OTA) update. The update allows users to manage and configure watch faces in the Android Wear app on their phone, and install watch faces from Google Play. Any handheld device running Android 4.3 or later will continue to work with all Android Wear devices.

Upgrade your watch faces

Developers are incredibly resourceful and we’re impressed with the watch faces you were able to create without any documentation at all. If you’ve already built a watch face for Android Wear using an unofficial approach, you should migrate your apps to the official API. The official API ensures a consistent user experience across the platform, while giving you additional information and controls, such as letting you know when the watch enters ambient mode, allowing you to adjust the position of system UI elements, and more. Using the new API is also necessary for your app to be featured in the Watch Faces collection on Google Play.

Deployment of watch faces to Google Play

We recommend you update your apps on Google Play as soon as the Android Wear 5.0 API 21 OTA rollout is complete, which we’ll announce on the Android Wear Developers Google+ community. It’s important to wait until the OTA rollout is complete because a Watch Face requiring API 21 will not be visible on a watch running API 20. Once your user gets the OTA, then the watch face will become visible. If you want to immediately launch your updates during the OTA rollout, make sure you set minSdkVersion to 20 in your wearable app, otherwise the app will fail to install for pre-OTA users. Once the rollout is complete, please transition your existing watch faces to the new API by January 31, 2015, at which point we plan to remove support for watch faces that don't use the official API.

Android Wear apps on Google Play

Starting today, you can submit any of your apps for designation as Android Wear apps on Google Play by following the Distributing to Android Wear guidelines. If your apps follow the criteria in the Wear App Quality checklist and are accepted as Wear apps on Play, it will be easier for Android Wear users to discover them. To opt-in for Android Wear review, visit the Pricing & Distribution section of the Google Play Developer Console.

In the few short months since we’ve launched Android Wear, developers have already written thousands of apps, taking advantage of custom notifications, voice actions, and fully native Android capabilities. Thanks to you, users have infinite ways to personalize their watches, choosing from six devices, a range of watch bands, and thousands of apps. With support for custom watch faces launching today, users will have even more choices in the future. These choices are at the heart of a rich Android Wear ecosystem and as we continue to open up core features of the platform to developers, we can’t wait to see what you build next.

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Categories: Programming

Google Play services and DEX method limits

Tue, 12/09/2014 - 18:42

Posted by Laurence Moroney, Developer Advocate

A constraint for some Android apps is the total number of methods that the underlying compiled .dex file can support. It’s limited by 16 bits, or 65,536 values.

When you include third-party libraries in your application, you will have all of their methods in your .dex file. Larger APIs, such as those included in Google Play services, will then begin eating into the limit very quickly.

You can learn more about this, and ways that you can work around it with the Android Studio 1.0 build system here.

Additionally, with Google Play services version 6.5 or later, it is possible for you to include Google Play services in your application using a number of smaller client libraries, so that only Google Play services APIs you use will get compiled into your .dex file, and therefore their methods won't count towards your method limit.

Prior to version 6.5, you would typically have a line like this in your build.gradle file:

compile 'com.google.android.gms:play-services:6.5.87'

Starting with version 6.5, of Google Play services, you’ll be able to pick from a number of individual APIs, and you can see which ones have their own include files in the documentation. For example, if all you want to use is Maps, you would instead have:

compile 'com.google.android.gms:play-services-maps:6.5.87'

Note that this will transitively include the ‘base’ libraries, which are used across all APIs. You can include them independently with the following line:

compile 'com.google.android.gms:play-services-base:6.5.87'

The complete list of API names is below. More details can be found on the Android Developer site.

com.google.android.gms:play-services-base:6.5.87
com.google.android.gms:play-services-ads:6.5.87
com.google.android.gms:play-services-appindexing:6.5.87
com.google.android.gms:play-services-maps:6.5.87
com.google.android.gms:play-services-location:6.5.87
com.google.android.gms:play-services-fitness:6.5.87
com.google.android.gms:play-services-panorama:6.5.87
com.google.android.gms:play-services-drive:6.5.87
com.google.android.gms:play-services-games:6.5.87
com.google.android.gms:play-services-wallet:6.5.87
com.google.android.gms:play-services-identity:6.5.87
com.google.android.gms:play-services-cast:6.5.87
com.google.android.gms:play-services-plus:6.5.87
com.google.android.gms:play-services-appstate:6.5.87
com.google.android.gms:play-services-wearable:6.5.87
com.google.android.gms:play-services-all-wear:6.5.87

Note: At the time of writing, the correct version to use is 6.5.87. As this is a very granular number, it will get updated quite quickly, so be sure the check the latest version when you are coding. Often people will use a ‘+’ to denote versions, such as 6.5.+ to use the latest 6.5 build. However, it’s typically discouraged to use a ‘+’ as it can lead to inconsistencies.

Also, there are some changes to the names of the libraries that will impact you if you build applications for Android Wear. Previously you may have used play-services-wearable to include the entire Google Play services library for your wearable, and if you want to continue doing so, you should now use play-services-all-wear instead. You can continue to use play-services-wearable which will instead give you just the Wearable Data Layer API (see here). Should you do this, and you want to continue working with other Google Play services features, such as the Location APIs on your wearable, you would need to add play-services-location.

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Categories: Programming