26 June 2014

Android L Developer Preview and Android Studio Beta

By Jamal Eason, Product Manager, Android

At the Google I/O keynote yesterday we announced the L Developer Preview — a development version of an upcoming Android release. The Developer Preview lets you explore features and capabilities of the L release and get started developing and testing on the new platform. You can take a look at the developer features and APIs in the API Overview page.

Starting today, the L Developer Preview is available for download from the L Developer Preview site. We're also announcing that Android Studio is now in beta, and making great progress toward a full release.

Let’s take a deeper dive into what’s included in the preview and what it means for you as a developer as you prepare your apps for the next Android release.

What’s in the L Developer Preview

The L Developer Preview includes updated SDK tools, system images for testing on an emulator, and system images for testing on a Nexus 5 or Nexus 7 device.

You can download these components through the Android SDK Manager:

  • L Developer Preview SDK Tools
  • L Developer Preview Emulator System Image - 32-bit (64-bit experimental emulator image coming soon)
  • L Developer Preview Emulator System Image for Android TV (32-bit)

(Note: the full release of Android Wear is a part of Android KitKat, API Level 20. Read more about Android Wear development here.)

Today, we are also providing system image downloads for these Nexus devices to help with your testing as well:

  • Nexus 5 (GSM/LTE) “hammerhead” Device System Image
  • Nexus 7 [2013] - (Wifi) “razor” Device System Image

You can download both of these system images from the L Developer Preview site.

With the SDK Tools, and Nexus device images, you can get a head start on testing out your app on the latest Android platform months before the official launch. You can use the extra lead time to take advantage of all the new app features and APIs in your apps. The Nexus device images can help you with testing, but keep in mind that they are meant for development purposes only and should not be used on a production device.

Notes on APIs and publishing

The L Developer Preview is a development release and does not have a standard API level. The APIs are not final, and you can expect minor API changes over time.

To ensure a great user experience and broad compatibility, you can not publish versions of your app to Google Play that are compiled against L Developer Preview. Apps built for L Developer Preview will have to wait until the full official launch to publish on Google Play.

Android Studio Beta

To help you develop your apps for the upcoming Android version and for new Android device types, we’re also happy to announce Android Studio Beta. Android Studio Beta helps you develop apps by enabling you to:

  • Incorporate the new material design and interaction elements of the L Developer Preview SDK
  • Quickly create and build apps with a new app wizard and layout editor support for Android Wear and Android TV

Building on top of the build variants and flavors features we introduced last year, the Android Studio build system now supports creating multiple apks, such as for devices like Android Wear. You can try out all the new features with the L Developer Preview by downloading the Android Studio Beta today.

How to get started

To get started with the L Developer Preview and prepare your apps for the full release, just follow these steps:

  1. Try out Android Studio Beta
  2. Visit the L Developer Preview site
  3. Explore the new APIs
  4. Enable the material theme and try out material design on your apps
  5. Get the emulator system images through the SDK Manager or download the Nexus device system images.
  6. Test your app on the new Android Runtime (ART) with your device or emulator
  7. Give us feedback

As you use the new developer features and APIs in the L Developer Preview, we encourage you to give us your feedback using the L Developer Preview Issue Tracker. During the developer preview period, we aim to incorporate your feedback into our new APIs and adjust features as best as we can.

You can get all the latest downloads, documentation, and tools information from the L Developer Preview site on developer.android.com. You can also check our Android Developer Preview Google+ page for updates and information.

We hope you try the L Developer Preview as you start building the next generation of amazing Android user experiences.

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25 June 2014

Google I/O: Design, Develop, Distribute

By Monica Tran, Head of Developer Marketing

Today at Moscone, we kicked off our 7th annual Google I/O. This year, we’re focusing on three key themes: design, develop, distribute, helping you build your app from start to finish.

It’s been amazing to see how far you’ve come: in fact, since the last Google I/O, we’ve paid developers more than $5 billion, a testament to the experiences you’re creating. In the keynote, we had a number of announcements geared towards meeting the user wherever they go: on the TV, in the car and on your wrist. Below is a taste of some of the goodies we unveiled to help you along the way.

DESIGN

  • Material design — we introduced material design, which uses tactile surfaces, bold graphic design, and fluid motion to create beautiful, intuitive experiences.
  • L-Release of Android, with material design — Bringing material design to Android is a big part of the L-Release of Android: we’ve added the new Material theme (which you can apply to your apps for a new style) and the ability to specify a view’s elevation, allowing you to cast dynamic, real-time shadows in your apps.
  • Bringing material design to Polymer — As a developer, you’ll now have access to all the capabilities of material design via Polymer, bringing tangibility, bold graphics, and animations to your applications on the web, all at 60fps.

DEVELOP

  • Android L Developer Preview — Get extra lead time to make great apps for the next version of Android, with lots of new APIs to make Android simpler and more consistent on screens everywhere
  • Google Play services 5.0 is rolling out worldwide with great new features for developers.
  • Android TV SDK — Explore, learn and build apps and games for the biggest screen in the home. Your hard work will pay off in the fall when Asus, Razer and other partners launch their first Android TV devices.
  • Google Cast SDK — Help users find your content more easily with the improved Google Cast SDK developer console, which lets your app get discovered on chromecast.com/apps and on Google Play.
  • Android Auto SDK coming — Bring your app experience to the car by extending your existing app with Android Auto APIs. Be in millions of cars — with just one app.
  • Google Fit — An open fitness platform giving users control of their fitness data so that developers can focus on building smarter apps and manufacturers can focus on creating amazing devices.
  • Gaming — Learn what's new about Google Play Games and the Android platform to take games to the next level.
  • Google Cloud Platform — Get help with debugging, tracing, and monitoring applications in with new developer productivity tooling. Also, try Cloud Dataflow, a new fully managed service that simplifies the process of creating data pipelines.
  • The new Gmail API — Add Gmail features to your app with RESTful access to threads, messages, labels, drafts and history.
  • Android features for Enterprise — Secure apps and data without complicating the user experience. Build for the enterprise with no changes to the apps you're already developing. Learn more here.

DISTRIBUTE

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New in Android: L Developer Preview and Google Play Services 5.0

By Jamal Eason, Product Manager, Android

Earlier today, at Google I/O, we showed a number of projects we’ve been working on to the thousands of developers in the audience and the millions more tuning in on the livestream. These projects extend Android to the TV (Android TV), to the car (Android Auto) and to wearables (Android Wear), among others.

At Google, our focus is providing a seamless experience for users across all of the screens in their lives. An important component to that is making sure that you as developers have all of the tools necessary to easily deploy your apps across to those screens. Increasingly, Android is becoming the fabric that weaves these experiences together, which is why you’ll be excited about a number of things we unveiled today.

Android L Developer Preview

For the first time since we launched Android, we’re giving you early access to a development version of an upcoming release. The L Developer Preview, available starting tomorrow, lets you explore many of the new features and capabilities of the next version of Android, and offers everything you need to get started developing and testing on the new platform. This is important because the platform is evolving in a significant way — not only for mobile but also moving beyond phones and tablets. Here are a few of the highlights for developers:

  • Material design for the multiscreen world — We’ve been working on a new design language at Google that takes a comprehensive approach to visual, motion, and interaction design across a number of platforms and form factors. Material design is a new aesthetic for designing apps in today’s multi-device world. The L Developer Preview brings material design to Android, with a full set of tools for your apps. The system is incredibly flexible, allowing your app to express its individual character and brand with bold colors and a variety of responsive UI patterns and themeable elements.
  • Enhanced notifications — New lockscreen notifications let you surface content, updates, and actions to users at a glance, without unlocking. Visibility controls let you manage the types of information shown on the lockscreen. Heads-up notifications display content and actions in a small floating window that’s managed by the system, no matter which app is in the foreground. Notifications are material themed and you can express your brand through accent colors and more.
  • Document-centric Recents — Now you can organize your app by tasks and present these concurrently as individual “documents” in the Recents screen. Users can flip through Recents to find the specific task they want and then jump deep into your app with a single tap.
  • Project Volta — New tools and APIs help your app run efficiently and conserve power. Battery Historian is a new tool that lets you visualize power events over time and understand how your app is using battery. A job scheduler API lets you set the conditions under which your background tasks and other jobs should run, such as when the device is idle or connected to an unmetered to a charger, to minimize battery impact.
  • BLE Peripheral Mode — Android devices can now function in Bluetooth Low Energy (BLE) peripheral mode. Apps can use this capability to broadcast their presence to nearby devices — for example, you can now build apps that let a device to function as a pedometer or health monitor and transmit data to another BLE device.
  • Multi-networking — Apps can work with the system to dynamically scan for available networks with specific capabilities and then automatically connect. This is useful when you want to manage handoffs or connect to a specialized network, such as a carrier-billing network.
  • Advanced camera capabilities — A new camera API gives you new capabilities for image capture and processing. On supported devices, your app can capture uncompressed YUV capture at full 8 megapixel resolution at 30 FPS. The API also lets you capture raw sensor data and control parameters such as exposure time, ISO sensitivity, and frame duration, on a per-frame basis.
  • New features for game developers — Support for OpenGL ES 3.1, gives you capabilities such as compute shaders, stencil textures, and texture gather for your games. Android Extension Pack (AEP) is a new set of extensions to OpenGL ES that bring desktop-class graphics to Android. Games will be able to take advantage of tessellation and geometry shaders, and use ASTC texture compression across multiple GPU techonolgies.
  • Android Runtime (ART) — The L Developer Preview introduces the Android Runtime (ART) as the system default. ART offers ahead-of-time (AOT) compilation, more efficient garbage collection, and improved development and debugging features. In many cases it improves performance of the device with no action required by the developer.
  • 64-bit support — The L Developer Preview adds support for 64-bit ABIs, for additional address space and improved performance with certain compute workloads. Apps written in the Java language can run immediately on 64-bit architectures with no modifications required. To support apps using native code, we’re also releasing an updated NDK that includes 64-bit support.

Watch for more details coming out tomorrow (26 June) on what’s in the L Developer Preview and how to get it.

Google Play Services 5.0

Along with the L Developer Preview, we also announced a new version of Google Play services that brings new capabilities and the latest optimizations to devices across the Android ecosystem. Google Play services ensures that you can build on the latest features from Google for your users, with the confidence that those services will work properly everywhere. The latest version has begun rolling out and here are some of the highlights:

  • Services for Android wearables — Your apps can more easily communicate and sync with code running on Android wearables through an automatically synchronized, persistent data store and a reliable messaging interface.
  • Play Games services — Build a great gaming experience with Quests, which allow event-based challenges for players to complete for rewards, Saved Games (a snapshot API allow synchronization of game data along with a cover-image and description), and Game Profile (providing experience points for players).
  • App Indexing API — Surface deep content in your native mobile applications on Google search and drive additional user engagement.
  • Google Cast — Use media tracks to enable closed-caption support for Chromecast.
  • Drive — Sort query results, create offline folders, and select any mime type in the file picker by default.
  • Wallet — Build a "Save to Wallet" button for offers directly into your app; use geo-fenced in-store notifications to prompt the user to show and scan digital cards. Split tender allows payment to be split between Wallet Balance and a credit/debit card in Google Wallet.
  • Analytics — Get insights into the full user journey and understand how different user acquisition campaigns are performing with Enhanced Ecommerce, letting you measure product impressions, product clicks, and more.
  • Mobile Ads — Use improved in-app purchase ads and integrations for the Play store in-app purchase API client.
  • Dynamic Security Provider — Offers an alternative to the platform's secure networking APIs that can be updated more frequently, for faster delivery of security patches.

We expect the rollout of Google Play services 5.0 to take several days, after which time you’ll be able to get started developing with these new APIs.

Join us at the Google I/O sessions

If you’d like to learn more, join us for sessions on Android development, material design, game development, and more. You’ll find the full session list on the Google I/O 2014 site, and you can filter the schedule to find livestreamed sessions of interest.

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Games at Google I/O '14: Everyone's Playing Games

By Greg Hartrell, Product Manager, Google Play games

With Google I/O ‘14 here, we see Android and Google Play as a huge opportunity for game developers: 3 in 4 Android users are playing games, and with over one billion active Android users around the world, games are reaching and delighting almost everyone.

At Google, we see a great future where mobile and cloud services bring games to all the screens in your life and connect you with others. Today we announced a number of games related launches and upcoming technologies across Google Play Games, the Android platform and its new form factors.

Google Play Games

At last year’s Google I/O, we announced Google Play Games -- Google’s online game platform, with services and user experiences designed to bring players together and take Android and mobile games to the next level.

Google Play Games has grown at tremendous speed, activating 100 million users in the past 6 months. It’s the fastest growing mobile game network, and with such an incredible response, we announced more awesome enhancements to Google Play Games today.

Game Profile

The Play Games app now gives players a Game Profile, where they earn points and vanity titles from unlocking achievements. Players can also compare their profile with friends. Developers can benefit from this meta-game by continuing to design great achievements that reward players for exploring all the content and depth of their game.

Quests and Saved Games

Two new game services will launch with the next update for Google Play Services on Android, and through the Play Games iOS SDK:

  • Quests is a service that enables developers to create online, time-based goals in their games without having to launch an update each time. Now developers can easily run weekend or daily challenges for their player community, and reward them in unique ways.
  • Saved Games is a service that stores a player’s game progress across many screens, along with a cover image, description and total time played. Players never have to play level 1 again by having their progress stored with Google, and cover images and descriptions are used in Play Games experiences to indicate where they left off and attract them to launch their favorite game again.

We have many great partners who have started integrating Quests and Saved Games, here are just a few current or upcoming games.

More tools for game developers

Other developer tools are now available for Play Games, including:

  • Play Games Statistics — Play Games adopters get easy effort game analytics through the Google Play Developer console today, including visualization of Player & Engagement statistics. What’s new is aggregated player demographic information for signed-in users, so you can understand the distribution of your player’s ages, genders and countries.
  • Play Games C++ SDK is updated with more cross-platform support for the new services and experiences we announced. Cocos2D-x, a popular game engine, is an early adopter of the Play Games C++ SDK bringing the power of Play Games to their developers.

Game enhancements for the Android Platform

With the announcement of the developer preview of the Android L-release, there are some new platform capabilities that will make Android an even more compelling platform for game development.

  • Support for OpenGL ES 3.1 in the L Developer Preview — Introducing powerful features like compute shaders, stencil textures, and texture gather, enables more interesting physics or pixel effects on mobile devices. Additional API and shading language improvements improve usability and reduce overhead.
  • Android Extension Pack (AEP) in the L Developer Preview — a new set of extensions to OpenGL ES that bring desktop class graphics to Android. Games will be able to take advantage of tessellation and geometry shaders, and use ASTC texture compression.

    We're pleased to be working with different GPU vendors to adopt AEP including Nvidia, ARM, Qualcomm, and Imagination Technologies.

  • Google Gamepad standards — We recently published a standard for gamepad input for OEMs and partners who create and enable these awesome input devices on Android. The standard makes this input mechanism compatible across Google platforms on Android, Chrome and Chromebooks. You can learn more here: Supporting Game Controllers.

Play Games on Android TV

And Google's game network is a part of the Android TV announcement — so think of Android on a TV, with a rich interface on a large screen, and fun games in your living room! Players will be able to earn achievements, climb leaderboards and play online with friends from an Android TV. This is only available through the developer preview, so game developers seeking a hardware development kit (the ADT-1) can make a request at http://developer.android.com/tv.

Updates rolling out soon

That’s a lot of games announcements! Our Play Games changes will roll out over the next few weeks with the update of Google Play Services and the Play Games App, and Android L-release changes are part of the announced developer preview. This gets us a big step closer to a world where Android and our cloud services enable games to reach all the screens in your life and connect you with others.

Greg Hartrell is the lead product manager for Google Play Games: Google's game platform that helps developers reach and unite millions of players. Before joining Google, he was VP of Product Development at Capcom/Beeline, and prior to that, led product development for 8 years at Microsoft for Xbox Live/360 and other consumer and enterprise product lines. In his spare time, he enjoys flying birds through plumbing structures, boss battles and pulling rare objects out of mystery boxes.

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Building Successful Global App Businesses

By: Purnima Kochikar, Director, Google Play Apps & Games

With over 1 billion active Android users, an increasing number of developers like you are building successful global businesses on Google Play. Since the last Google I/O, we’ve also paid out more than $5 billion to developers.

This week at Google I/O, we announced new ways to help you build a successful business. These solutions work together at scale to help you find more users, understand and engage them, and effectively convert your active users into buyers.

Build an engaging app

Last year, Google Play became an even better place to try new ideas. Since May 2013, Google Play offers Alpha and Beta Testing so that you can engage users early to get feedback on your new app. Feedback provided by users is private, allowing you to fix issues before publicly launching the app, and without impacting your public ratings and reviews. Over 80,000 apps on Google Play are actively using beta testing. You can also ensure new versions get a positive response by updating through staged rollouts.

Scale operations

As your app business grows, you dedicate more time to release management. Today we announced the Google Play Developer Publishing API to help you scale your release operations. The new API will let you upload APKs, manage your in-app products and localized store listings. You will be able to integrate publishing operations with your release processes and toolchain through a RESTful API. With the Google Play Developer Publishing API you’ll spend less time managing your releases and more time managing your business. This API is currently in closed beta and we look forward to making it available to all developers.

Actionable insights

The Google Play Developer Console now offers more actionable insights into your app’s performance by sending you email notifications for Alerts and providing Optimization Tips. We’re also offering new revenue metrics including number of buyers and average revenue per paying user. You’ll also be able to export user reviews for further analysis. Click on Announcements in the Developer Console for a list of new features.

For game developers, we recently launched enhanced Play Games statistics on the Google Play Developer Console. You get a daily dashboard that visualizes player and engagement statistics for signed in users, including daily active users, retention analysis, and achievement and leaderboard performance.

Enhance discovery and engagement

With AdWords, we're building a robust platform to help you promote your app and drive re-engagement. This week we are launching Installed App Category Targeting, a new way to promote your app to new users. It helps you reach potential customers across the AdMob network who have already installed apps from related categories on Google Play and other app stores. For example, an action-oriented game developer may wish to reach users who have previously installed apps from the category Action & Adventure Games.

Ads can also remind users about the apps they already have. Through Google mobile display and search ads deep linking, you can re-engage users who have already installed your Android app by taking them directly to specific pages in the app. Let’s say someone has the Hotel Tonight app installed on their phone. If they search Google for “hotels in San Francisco," they'll see an ad that will open Hotel Tonight app and take them directly to a list of San Francisco hotels.

This deep-linking is also available through search for all apps that implement app indexing. If a user with the Walmart Android app searches for “Chromecast where to buy”, they’ll go directly to the Chromecast page in the Walmart app. The new App Indexing API is now open to all Android developers, globally. Get started now.

New services for game developers

For game developers using Play Games, we announced a new Game Profile that is automatically customized based on the gameplay and achievements earned in those games. Since its launch last year, users have loved saving their game progress in the cloud. We’re now evolving this feature to Saved Games, where users can save up to 3 “bookmarks” of their progress in the Play Games app, complete with images and descriptions. Finally, we announced a new service called Quests — it you run online, time-based goals in your game; for example, players can collect bunch of in-game items on a specific day, and the quests services coordinates with your game to know who completed the goal. These APIs run events for your players, and reward them, without the need to update your game.

New monetization tools

Today, we announced that users who have set up Direct Carrier Billing on their smartphone can also make purchases on Google Play from their tablet, charging to the same mobile phone bill. In addition to our recent launch of payments through PayPal, these new user payment options expand monetization opportunities for your apps.

As announced earlier this year, Google Analytics is now directly available in the AdMob interface, giving you powerful segmentation tools to determine the best monetization strategy for each user. For example, you might want to display in-app purchase ads to users most interested in buying, while showing regular ads to those less likely to buy right now. Once you’ve segmented your audience in this way, you can use AdMob to build interstitial ads that promote in-app purchase items to users at a point in your app that’s useful to them. This creates a more customized experience for users, can help prolong engagement and grow in-app purchase revenue. Learn more.

Join us

If you're at Google I/O 2014, please join us at our breakout sessions today and tomorrow, where we'll be talking about these features in much more detail. (Add us to your calendar!) And if you can't make I/O, you can always join us on the livestream or watch the videos online later.

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Cast Away with Android TV and Google Cast

By Dave Burke and Majd Bakar, Engineering Directors and TV Junkies

Last summer, we launched Chromecast, a small, affordable device that lets you cast online video, music and anything from the web to your TV. Today at Google I/O, we announced Android TV, the newest form factor to the Android platform, and a way to extend the reach of Google Cast to more devices, like televisions, set-top boxes and consoles.

Check out Coming to a Screen Near You for some details on everything we’re doing to make your TV the place to be.

For developers though--sorry, you don’t get to unwind in front of the TV. We need you to get to work and help us create the best possible TV experience, with all of the new features announced at I/O today.

Get started with Android TV

In addition to Google Cast apps that send content to the TV, you can now build immersive native apps and console-style games on Android TV devices. These native apps work with TV remotes and gamepads, even if you don’t have your phone handy. The Android L Developer Preview SDK includes the new Leanback support library that allows you to design smoother, simpler, living room apps.

And this is just the beginning. In the fall, new APIs will allow you to cast directly to these apps, so users can control the app with the phone, the remote, or even their Android Wear watch. You’ll also start seeing Android TV set-top boxes, consoles and televisions from Sony, TP Vision, Sharp, Asus, Razer and more.

Help more users find your Google Cast app

We want to help users more easily find your content, so we’ve improved the Google Cast SDK developer console to let you upload your app icon, app name, and app category for Android, iOS and Chrome. These changes will help your app get discovered on chromecast.com/apps and on Google Play.

Additional capabilities have also been added to the Google Cast SDK. These include: Media Player Library enhancements, bringing easier integration with MPEG-DASH Smooth Streaming, and HLS. We’ve also added WebAudio & WebGL support, made the Cast Companion Library available, and added enhanced Closed Caption support. And coming soon, we will add support for queuing and ID delegation.

Ready to get started? Visit developer.android.com/tv and developers.google.com/cast for the SDKs, style guides, tutorials, sample code, and the API references. You can also request an ADT-1 devkit to bootstrap your Android TV development.

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18 June 2014

New ways to connect your app to the Cloud using Android Studio and Google Cloud Platform

Posted by Manfred Zabarauskas, Product Manager on Google Cloud Platform

Many Android developers like Snapchat or Pulse build and host their app backends on the Google Cloud Platform, and enjoy automatic management, with simple expansion to support millions of users.

To quickly add a Google Cloud Platform backend to your Android app, you can now use a number of built-in features in Android Studio 0.6.1+.

Google App Engine backend module templates

Google App Engine enables you to run your backend applications on Google's infrastructure, without ever requiring you to maintain any servers.

To simplify the process of adding an App Engine backend to your app, Android Studio now provides three App Engine backend module templates which you can add to your app. You can find them under "New → Module" menu:

  1. App Engine Java Servlet Module provides a simple App Engine Java backend servlet with minimal boilerplate code,
  2. App Engine Java Endpoints Module template leverages Google Cloud Endpoints for your backend, and includes automated object marshalling/unmarshalling, generation of strongly-typed Java client libraries and so on,
  3. App Engine Backend with Google Cloud Messaging includes both Google Cloud Endpoints and Google Cloud Messaging integration, which enables additional features like push notifications.

When you choose one of these template types, a new Gradle module with your specified module/package name will be added to your project containing your new App Engine backend. All of the required dependencies/permissions will be automatically set up for you.

You can then run it locally (on http://localhost:8080) by selecting the run configuration with your backend's module name, as shown in the image below.

For more information about these backend templates, including their deployment live to App Engine and code examples which show how to connect your Android app to these backends, see their documentation on GitHub. (Also, the code for these templates lives in the same GitHub repository, so do not hesitate to submit a pull request if you have any suggestions!)

Built-in rich editing support for Google Cloud Endpoints

Once you have added the backend module to your Android application, you can use Google Cloud Endpoints to streamline the communication between your backend and your Android app. Cloud Endpoints automatically generate strongly-typed client libraries from simple Java server-side API annotations, automate Java object marshalling to and from JSON, provide built-in OAuth 2.0 support and so on.

As a concrete example, "App Engine Java Endpoints Module" contains a simple annotated Endpoints API at <backend-name>/src/main/java/<package-name>/MyEndpoint.java file (shown below):

import javax.inject.Named;

@Api(name = "myApi",
     version = "v1",
     namespace = @ApiNamespace(ownerDomain = "<package-name>",
                               ownerName = "<package-name>",
                               packagePath=""))
public class MyEndpoint {
    @ApiMethod(name = "sayHi")
    public MyBean sayHi(@Named("name") String name) {
        MyBean response = new MyBean();
        response.setData("Hi, " + name);
        return response;
    }
}

On deployment, this annotated Endpoints API definition class generates a RESTful API. You can explore this generated API (and even make calls to it) by navigating to Endpoints API explorer as shown in the image below:

Google APIs explorer is available at http://localhost:8080/_ah/api/explorer once you deploy your app. Color overlays in this screenshot match the colors in the API snippet above (MyEndpoint.java).

To simplify calling this generated API from your Android app, Android Studio will automatically set up your project to automatically include all compile dependencies and permissions required to consume Cloud Endpoints, and will re-generate strongly-typed client libraries if your backend changes. This means that you can start calling the client libraries from your Android app immediately after defining the server-side Endpoints API:

Code completion for automatically generated, strongly-typed client libraries. Color overlays match the colors in the API snipped above (MyEndpoint.java)

As server-side Endpoints API definitions have to conform to a number of syntactic rules, Android Studio also includes a number of Endpoints-specific inspections and quick-fixes, which help you to avoid mistakes when writing Endpoints APIs.

For example, "@Named" annotation is required for all non-entity type parameters passed to server-side methods. If you forget to add this annotation when modifying sayHi method in MyEndpoint.java file, Android Studio will underline the problematic statement as-you-type:

Furthermore, to help you easily fix the problems with Cloud Endpoints, Android Studio will provide quick-fixes for the most common Cloud Endpoints development mistakes. To see these quick-fix suggestions, press Alt + Enter if you're running on Linux/Windows or ⌥ + Enter if you're running on Mac:

As expected, choosing the first quick-fix ("Add @Named") will automatically add "@Named" annotation to method's parameter, solving this problem in two key presses.

The underlying work-horses: Gradle, and Gradle plug-in for App Engine

Under the hood, Gradle is used to build both your app and your App Engine backend. In fact, when you add an App Engine backend to your Android app, an open-source App Engine plug-in for Gradle is automatically downloaded by Android Studio, and common App Engine tasks become available as Gradle targets. This allows you to use the same build system across your IDE, command-line or continuous integration environments.

For example, to deploy your backend to App Engine from Android Studio, you can launch the "appengineUpdate" task from the "Gradle tasks" tool window:

Similarly, if you want to integrate your backend's deployment into your command-line scripts, simply launch "./gradlew backend:appengineUpdate" command from your project's root directory.

Try out a codelab, or see these features live at Google I/O 2014!

If you want to give these features a spin in a more guided environment, try out our Cloud Endpoints codelab for Android. We will also be demonstrating some of these features live at Less Code, More Services, Better Android Apps session in Google I/O 2014 (as well as some of the new and even more exciting stuff), so don't forget to tune in!

We look forward to your questions or feedback, and learning about the amazing applications you have built using Android Studio and Google Cloud Platform. You can find us lurking on StackOverflow's App Engine and Cloud Endpoints forums!

17 June 2014

FlatBuffers: A Memory-Efficient Serialization Library

By Wouter van Oortmerssen, Fun Propulsion Labs at Google

Game developers, we've just released FlatBuffers, a C++ serialization library that allows you to read data without unpacking or allocating additional memory, as an open source project.

FlatBuffers stores serialized data in buffers in a cross-platform way, supporting format evolution that is fully forwards and backwards compatible through a schema. These buffers can be stored in files or sent across the network as-is, and accessed in-place without parsing overhead.

The FlatBuffers schema compiler and runtime is written in platform independent C++ with no library dependencies outside the STL, which makes it possible to use on any platform that has a C++ compiler. We have provided methods to build the FlatBuffers library, example applications, and unit tests for Android, Linux, OSX and Windows. The schema compiler can generate code to read and write FlatBuffers binary files for C++ and Java. It can additionally parse JSON-formatted data into type-safe binaries.

Game developers can use this library to store game data with less overhead than alternative solutions (e.g. Protocol Buffers or JSON). We’re excited about the possibilities, and want to hear from you about how we can make this even better!

Download the latest release from the FlatBuffers page in GitHub and join our discussion list!

Fun Propulsion Labs is a team within Google that's dedicated to advancing gaming on Android and other platforms.

03 June 2014

An Android Wear Design Story

By Roman Nurik and Timothy Jordan, Design and Developer Advocates on Android Wear

A few weeks ago, Timothy and I were chatting about designing apps for wearables to validate some of the content we’re planning for Google I/O 20141. We talked a lot about how these devices require scrutiny to preserve user attention while exposing some unique new surface areas for developers. We also discussed user context and how the apps we make should be opportunistic, presenting themselves in contexts where they’re useful; it’s more important than ever to think of apps on wearable devices not as icons on a grid but rather as functional overlays on the operating system itself.

But while I’d designed a number of touch UIs for Android in the past and Timothy had a ton of experience with Glass, neither of us had really gone through the exercise of actually designing an app for Android Wear. So we set out to put our ideas in practice and see what designing for this new platform is like.

Before we got started, we needed an idea. Last year, I participated in an informal Glass design sprint in NYC run by Nadya Direkova, and my sprint team came up with a walking tour app. The idea was you’d choose from a set of nearby tours, walk between the stops, and at each stop on the tour, learn about the destination.

My rough mocks of a walking tour app from a Glass design sprint.

While the design sprint ended at rough mocks, the idea stuck around in my mind, and came up again during this exercise. It seemed like a perfect example of a contextually aware app that could enhance your Android Wear experience.

Designing a walking tour app for Android Wear

We started fleshing out the idea by thinking through the app’s entry points: how will users “launch” this app? While exposing a “start XYZ walking tours app” voice command is pretty standard, it’d be interesting to also suggest nearby walking tours as you go about your day by presenting notifications in the user’s context stream. These notifications would be “low priority,” so you’d only see them after addressing the more important stuff like text messages from friends. And with today’s geofencing and location functionality in Google Play services, this type of contextual awareness is possible in a battery-friendly way.

At this point we were pretty excited and decided to begin mocking up the UI. Rather than starting from scratch, we used Taylor Ling’s excellent Android Wear 0.1 design template as a baseline, which includes templates for both square and round devices. We started with square since we were most familiar with rectangle UI design:

Idea: You get a notification in the context stream when a walking tour is available nearby.

I’ve got to admit, it was pretty thrilling designing in such a constrained environment. 140x140 dp (280x280 px @ XHDPI) isn’t a lot of space to work with, so you need to make some tough choices about when and how to present information. But these are exactly the types of problems that make design really, really fun. You end up spending more time thinking and less time actually pushing pixels around in Photoshop or Sketch.

We pretty quickly fleshed out the rest of the app for square devices. They included just a handful of additional screens: a dynamic notification showing the distance to your next stop, and a 4-page detail screen when you arrive at the tour stop, where you can spend a few moments reading about where you’re standing.

A notification guiding you to your next stop, and a multi-page stop detail screen for learning about the stop when you get there.

Seeing our design in real life

Here’s the thing—there’s only so much you can do in Photoshop. To truly understand a platform as a designer, you really need to use (and ideally live with) a real device, and see your work on that device. Only then can you fully evaluate the complexity of your flows, the size of your touch targets, or the legibility of your text.

Luckily, Timothy and I both had test devices—I sported an LG G Watch prototype and Timothy carried a Moto 360 prototype. We then needed a way to quickly send screens to our devices so we could iterate on the design. A few years ago I’d published the Android Design Preview tool that lets you mirror a part of your screen to a connected Android device. Much to our delight, the tool worked great with Android Wear! After seeing our mocks show up on my LG G Watch, we made a few small tweaks and felt much more confident that the overall idea “felt right” on the wrist.

Android Design Preview mirrors a part of your computer screen to an Android device. It’s especially awesome seeing your UI running on an LG G Watch prototype.

Designing for round devices

We’d never designed round UIs before, so we weren’t sure what this new adventure would be like. Quite frankly, it ended up being unbelievably easy: tweaking all 8 of our screen mocks for round took under an hour. When you’re only showing the most important 2 or 3 pieces of information on screen at a time, that’s only 2 or 3 pieces of information you need to optimize for round devices. All in all, there were only a few types of minor tweaks we made:

  • Scaled up backgrounds to 160x160 dp (320x320 px @ XHDPI)
  • Bumped up content margins from 12dp on square to 26dp on round; this means content was 116x116 dp on square and only a little smaller at 108x108 dp on round
  • Pushed down circular actions like “Continue tour” to better vertically center with the watch frame
  • Center-aligned certain short snippets of text on round devices as opposed to left-aligning on square
  • Dropped the side padding for context stream cards (the platform automatically does this for notifications, so there isn’t any actual work to do here)
These weren’t completely different layouts—rather, the same layout with slightly tweaked metrics.

It’s hard to articulate the excitement we felt when we mirrored the mocks to Timothy’s Moto 360 prototype with Android Design Preview. To put it lightly, our minds were blown.

There’s something special and awe-inspiring about seeing one of your UIs running on a round screen..

And that was it—with round and square mocks complete, and mirrored on our devices, we’d gotten our first glimpse at designing apps for this exciting new platform. Below are our completed mocks for the tour discovery and engagement flows, not a grid of app icons in sight. You can download the full PSDs here.

An eye-opening experience

Designing for Android Wear is pretty different from designing for the desktop, phones or tablets. Just like with Glass, you really need to think carefully about the information and actions you present to the user, and even more so about the contexts in which your app will come to the surface.

As a designer, that’s the fun part—working with constraints involving scarce resources like device size and user attention means it’s more important than ever to think deeply about your ideas and iterate on them early and often. The actual pixel-pushing part of the process is far, far easier.

So there we were, putting our ideas into practice, on real actual device prototypes that we could’ve only dreamed about only a few years ago. It was the most fun I’ve had designing UIs in a long time. Remember that feeling when you first dreamed up an app, mocked or even coded it up, and ran it on your Android phone? It was that same feeling all over again, but amplified, because you were actually wearing your app. I can’t wait for you all to experience it!

1 Have we mentioned #io14 will have tons of great content around both design and wearable computing? Make sure to tune in June 25th and 26th!

02 June 2014

New Demographic Stats in Google Play Games Services

By Ben Frenkel, Google Play Games team

Hey game developers, back in March you may remember we added new game statistics in the Google Play Developer Console for those of you who had implemented Google Play Games: our cross-platform game services for Android, iOS and the web.

Starting today, we're providing more insights into how your games are being used by adding country, age, and gender dimensions to the existing set of reports available in the Developer console. You’ll see demographics integrated into Overview stats as well as the Players reports for New and Active users.

In the Overview stats you can now see highlights of activity by age group, most active countries, and gender.

With a better understanding of your users’ demographic composition, you'll be able to make more effective decisions to improve retention and monetization. Here a few ways you could imagine using these new stats:

  • You just launched your new game globally, and expected it do particularly well in Germany. Using country demographic data, you see that Germany is much less active than expected. After some digging, you realize that your tutorial was not properly translated to German. Based on this insight, you immediately roll out a fix to see if you can improve active users in Germany.

In the Players stats section the new metrics reveal trends in how your app is doing across age groups, countries, and gender.

  • After Looking at your new demographics report you realize that your game is really popular with women in their mid-20s. Your in-app purchase data corroborates this, showing that the one female hero character is the most popular purchase. Empowered by this data, you race to add female hero characters to your game.

Additionally, if you're already using Google Play game services, there's no extra integration needed! By logging in to the Google Play Developer Console you can start using demographics to better inform your decisions today.