Android Studio 2.1 supports Android N Developer Preview

Posted by Jamal Eason, Product Manager, Android

With the launch Android N Developer Preview, we wanted to give you an easy and comprehensive way to build, test and validate your apps on the latest release with Android Studio. Built on the speed and feature enhancements of Android Studio 2.0, the stable release of Android Studio 2.1 includes updates to the IDE wizards, build system and Android Emulator so that you can try out new features and APIs of the developer preview including the new Jack compiler and Java 8 language support. In addition to support for the N Developer Preview, Android Studio 2.1 also includes performance improvements to Instant Run which leads to faster edit and deploy build speeds. If you are developing and validating your app with the N Developer Preview or want faster Instant Run speeds, you should download or update on the stable release channel to Android Studio 2.1.

Android Studio 2.1 includes the following new features:

• N Developer Preview Support: Android Studio 2.1 is the best IDE to test and validate your app with the N Developer Preview. Get the latest versions of the preview SDK, experiment with the new Java 8 support, and gain access to the only official Android Emulator able to run N Developer Preview Emulator System Images to help in your testing.
• Instant Run: For those of you who enjoyed the fast edit, build and deploy cycle with Android Studio 2.0, Instant Run now can now update incremental changes to your app code significantly faster.

Deeper Dive into the New Features

N Developer Preview

On top of new features and APIs of the N Developer Preview, Android Studio 2.1 release includes support for the new Jack compiler and support for Java 8. With the Jack compiler, lambdas, method references, compile-time type annotations, intersection types and type inference are available on all versions of the Android platform. Default and static methods and repeatable annotations are available on Android N and higher. To use Java 8 language features when developing with the N Developer Preview, you need to use the Jack compiler. The New Project Wizard [File→ New→ Project] generates the correct configurations for projects targeting the N.

Getting started with development is as easy generating a new project or updating a few settings in your existing project. Once you are ready to test, you can create a fresh Android Virtual Device (AVD) and run your app on the N Developer Preview using the new Android Emulator.

N Developer Preview on the new Android Emulator

Instant Run & General Build Performance Improvements

Instant Run and general build speed are now faster with two new features: incremental Java compilation and in-process dex.

In previous versions of Android Studio, a single line of Java code change will cause all the Java sources in the module to be recompiled. Now in Android Studio 2.1, incremental Java compilation is enabled by default to reduce compilation time by compiling only what is needed.

We are also speeding up build times by using in-process dex, which converts class files to dex files within the Gradle daemon process. This avoids the costly processing operation of creating separate dex processes. To use this feature, you will need to increase the amount of memory available to the Gradle daemon to at least 2GB (1 GB is the default). This feature will help speed up both incremental and full builds.

We’d appreciate your feedback as we continue to improve Instant Run and general build performance. We are going to keep working on making build times even faster in coming releases. Click here to learn even more about the build changes.

What's Next

Update

If you are using a previous version of Android Studio, you can check for updates on the Stable channel from the navigation menu (Help → Check for Update [Windows/Linux] , Android Studio → Check for Updates [OS X]). If you need a new copy of Android Studio, you can download it here.

Test and Validate Apps with N Developer Preview

After you update to or download Android Studio 2.1 and you want to test and develop your apps with the N Developer Preview, create a fresh Android Virtual Device (AVD) for the new Android emulator, and check out these additional setup instructions.

We appreciate any feedback on things you like, issues or features you would like to see. Connect with us -- the Android Studio development team -- on our Google+ page or on Twitter.

Building TV Channels

Posted by Josh Gordon, Developer Advocate

Channel surfing is a popular way of watching TV. You pick up the remote, lean back, and flip through channels to see what’s on. On Android TV, app developers can create their own channel-like experiences using the TV Input Framework.

To the user, the channels you create look and feel just like regular TV channel. But behind the scenes, they stream video over the internet. For example, you can create a channel from a video playlist.

Watch this DevByte for an overview of how to build to a channel, and see the sample app and developer training for more info. The sample shows how to work with a variety of media formats, including HLS, MPEG-Dash, and HTTP Progressive.

If you already have an app that streams video, consider also making your content available as a channel. It’s a great opportunity to increase engagement. We’re excited to see what you develop, and look forward to seeing your content on the big screen!

Protecting against unintentional regressions to cleartext traffic in your Android apps

Posted by Alex Klyubin, Android Security team

When your app communicates with servers using cleartext network traffic, such as HTTP, the traffic risks being eavesdropped upon and tampered with by third parties. This may leak information about your users and open your app up to injection of unauthorized content or exploits. Ideally, your app should use secure traffic only, such as by using HTTPS instead of HTTP. Such traffic is protected against eavesdropping and tampering.

Many Android apps already use secure traffic only. However, some of them occasionally regress to cleartext traffic by accident. For example, an inadvertent change in one of the server components could make the server provide the app with HTTP URLs instead of HTTPS URLs. The app would then proceed to communicate in cleartext, without any user-visible symptoms. This situation may go unnoticed by the app’s developer and users.

Even if you believe your app is only using secure traffic, make sure to use the new mechanisms provided by Android Marshmallow (Android 6.0) to catch and prevent accidental regressions.

New protection mechanisms

For apps which only use secure traffic, Android 6.0 Marshmallow (API Level 23) introduced two mechanisms to address regressions to cleartext traffic: (1) in production / installed base, block cleartext traffic, and (2) during development / QA, log or crash whenever non-TLS/SSL traffic is encountered. The following sections provide more information about these mechanisms.

Block cleartext traffic in production

To protect the installed base of your app against regressions to cleartext traffic, declare android:usesCleartextTraffic=”false” attribute on the application element in your app’s AndroidManifest.xml. This declares that the app is not supposed to use cleartext network traffic and makes the platform network stacks of Android Marshmallow block cleartext traffic in the app. For example, if your app accidentally attempts to sign in the user via a cleartext HTTP request, the request will be blocked and the user’s identity and password will not leak to the network.

You don’t have to set minSdkVersion or targetSdkVersion of your app to 23 (Android Marshmallow) to use android:usesCleartextTraffic. On older platforms, this attribute is simply ignored and thus has no effect.

Please note that WebView does not yet honor this feature.

And under certain circumstances cleartext traffic may still leave or enter the app. For example, Socket API ignores the cleartext policy because it does not know whether the data it transmits or receives can be classified as cleartext. Android platform HTTP stacks, on the other hand, honor the policy because they know whether traffic is cleartext.

Google AdMob is also built to honor this policy. When your app declares that it does not use cleartext traffic, only HTTPS-only ads should be served to the app.

Third-party network, ad, and analytics libraries are encouraged to add support for this policy. They can query the cleartext traffic policy via the NetworkSecurityPolicy class.

Detect cleartext traffic during development

To spot cleartext traffic during development or QA, StrictMode API lets you modify your app to detect non-TLS/SSL traffic and then either log violations to system log or crash the app (see StrictMode.VmPolicy.Builder.detectCleartextNetwork()). This is a useful tool for identifying which bits of the app are using non-TLS/SSL (and DLTS) traffic. Unlike the android:usesCleartextTraffic attribute, this feature is not meant to be enabled in app builds distributed to users.

Firstly, this feature is supposed to flag secure traffic that is not TLS/SSL. More importantly, TLS/SSL traffic via HTTP proxy also may be flagged. This is an issue because as a developer, you have no control over whether a particular user of your app may have configured their Android device to use an HTTP proxy. Finally, the implementation of the feature is not future-proof and thus may reject future TLS/SSL protocol versions. Thus, this feature is intended to be used only during the development and QA phase.

Declare finer-grained cleartext policy in Network Security Config

Android N offers finer-grained control over cleartext traffic policy. As opposed to android:usesCleartextTraffic attribute, which applies to all destinations with which an app communicates, Android N’s Network Security Config lets an app specify cleartext policy for specific destinations. For example, to facilitate a more gradual transition towards a policy that does not allow cleartext traffic, an app can at first block accidental cleartext only for communication with its most important backends and permit cleartext to be used for other destinations.

Next steps

It is a security best practice to only use secure network traffic for communication between your app and its servers. Android Marshmallow enables you to enforce this practice, so give it a try!

As always, we appreciate feedback and welcome suggestions for improving Android. Contact us at [email protected]. HTTPS, Android-Security

An Outsourcing Playbook for Android development

Posted by Rupert Whitehead, Developer Relations

We recently updated The Secrets to App Success on Google Play with tools and tips to help app and game developers grow successful businesses on Google Play. However, many great apps are created by agencies and freelancers on behalf of companies. Today, we’re releasing a new playbook to help companies of any size who are considering outsourcing their Android app development.

How do you choose an agency? What are the pitfalls you should avoid? What can you do to make your app successful? These are some of the questions tackled by the new Outsourcing Playbook that you can read on Google Play.

Let us know your feedback

Once you’ve checked out the guide, we’d love to hear your feedback so we can continue to improve our developer resources and support. Let us know what you think.

The Google Play Awards coming to Google I/O

Posted by Purnima Kochikar, Director, Apps and Games Business Development, Google Play

Google Play has seen tremendous growth over the past year, reaching more than 1 billion Android users across 190 countries. As a way to recognize our incredible developer community and highlight some of the best apps and games, we’re kicking off our first-ever Google Play Awards.

The program will showcase five nominees across 10 award categories and feature them in a dedicated collection on Google Play. Nominees were selected by a panel of experts on the Google Play team based on criteria emphasizing app quality, innovation, and having a launch or major update in the last 12 months. The winners of each category will be announced at Google I/O in May.

The full list of categories and nominees are below:

Standout Startup

Apps from new developers that offer a unique experience while achieving strong install growth. And the nominees are...

Dubsmash	Hopper	Musical.ly	Robinhood	Vrse

Standout Indie

Games from indie developers that focus on artistic design, high quality and innovative gameplay. And the nominees are...

Alphabear	Alto’s Adventure	Fast like a Fox	Neko Atsume: Kitty Collector	Prune

Best Families App

Apps or games with family friendly design that encourage creativity and exploration. And the nominees are...

Card Wars - Adventure Time	LEGO Jurassic World™	My Very Hungry Caterpillar	Thinkrolls 2	Toca Nature

Best Use of Material Design

First-class implementation of material design concepts that deliver an immersive and innovative user experience. And the nominees are...

Bring!	Robinhood	The Fabulous	Todoist	Vevo

Best Use of Google Play Game Services

High quality games with several strong GPGS feature implementations. And the nominees are...

Sea Battle 2	Table Tennis Touch	Tapventures	TowerMadness 2	Zombie Highway 2

Early Adopter

Early adopter of a nascent technology or platform, providing a delightful user experience. And the nominees are...

Glide	Mechanic Escape	Minecraft: Story Mode	World Around Me	Zumper

Go Global

Apps or games with great localization and culturalization, or subject matter appeal, across multiple regions. And the nominees are...

Dragon Ball Z Dokkan Battle	Freeletics Bodyweight	Memrise	Musixmatch	Pokémon Shuffle Mobile

Most Innovative

Apps or games offering a highly engaging novelty experience or unique benefit. And the nominees are...

Fast like a Fox	NYT VR	SmartNews	The Fabulous	This War of Mine

Best App

A true representation of beautiful design, intuitive UX and high user appeal, quality and rating. And the nominees are...

BuzzFeed News	Colorfy	Houzz	TuneIn Radio	Yummly

Best Game

Games with strong mechanics, informative tutorial, broad appeal and tasteful design. And the nominees are...

Alphabear	Clash of Kings	Clash Royale	MARVEL Future Fight	Star Wars™: Galaxy of Heroes

Join us live at the ceremony on May 19th at 7:00 pm PDT on stage 7 at Google I/O or via the live stream. You can also track the conversation on Twitter and G+ using the hashtags #io16.