With last month's release of the Android N Preview, the Tools team launched a preview release of Android Studio 2.1. Not only did the new version add support for the N Preview SDK, but it also brought a few important important and welcomed additions, including adoption and support for many of the language features in Java 8, a semi-official switch to the Jack compiler, an updated New Project wizard, and further improvements to the new and faster Android Emulator. As of today, Android Studio 2.1 has been promoted to Stable and is available to all developers.
The biggest advantage of updating and switching to the Jack compiler, aside from playing with new Android N APIs like Launcher Shortcuts, is probably the addition of Lambda Expressions. This is one of the major language features of Java 8, and because of its implementation, about the only one that is backward compatible to Android 2.3 Gingerbread. Most of the remaining Java 8 features will not work on versions older than Android N (API 24). However, if you're working on an app that can require N, take a look at default and static interface methods, repeatable annotations, and method references.
Developers updating from Android Studio 2.0 should also remember not to switch their gradle scripts to Jack if they actively use Instant Run in their projects–Jack doesn't support this feature yet. Judging by many of the comments on our site (and my own personal experiences), Instant Run tends to be fairly slow, unpredictable, and not particularly stable, so this is may not be a big sacrifice for many developers.
If you watched the video embedded above, you may have noticed the thing about the box. This is a callback to a bit about a mysterious box almost exactly 6 months ago with the release of Android Studio 1.5 to the Stable channel. As the video points out, there are some commonalities between this release and the 1.5 version; primarily that they both contained a number of bug fixes, and they immediately preceded a new Android version and a fairly major developer conference... in this case, Google I/O 2016 (nudge)(nudge). Shortly after that release, a preview of Android Studio 2.0 was launched with a boatload of new features. In case it's not completely obvious, they're not-so-subtly hinting that there's going to be a really big update to Android Studio announced at I/O. It will probably get some stage time during the keynote, then more thorough coverage during the What's new in Android development tools session on day 2. We'll be watching, so keep an eye out for announcements.
If you're ready to update to the new release, just open Android Studio and check for updates. If you're updating from v1.5 or older, you'll have to get a new installer from the Android Tools page. As always, it's also possible to keep multiple versions of Studio installed simultaneously, which may be important if you're working on a project that might fail to build or suffer unexpected issues on newer versions of Gradle.
- Android Developers Blog