Google launched the Android O developer preview 3.0 today. Its available for download now at developer.android.com and via the Android Beta Program. The preview includes an updated SDK with system images for Nexus 5X, Nexus Player, Nexus 6P, Pixel C, Pixel, Pixel XL and the official Android Emulator. You can also get an emulator for testing Android Wear 2.0 on Android O. The main highlight is with this preview Android O APIs are now final.
Google launched the first Android O developer preview in March and the second developer preview in May. Google is planning to release one last preview with near-final system images in July . Final release will be “later this summer” (in Q3 2017).
Android O offers of alot of new features like background limits, notification channels and dots, Picture in Picture, Autofill APIs, XML font resources, emoji compatibility, downloadable fonts, autosizing textview, adaptive icons, Webview enhancements, high-quality Bluetooth audio codecs, AAudio API, wide-gamut color for apps, and Google Play Protect and Java 8 APIs and runtime optimizations. Google is also promising faster boot times and smoother apps with OS optimizations.
Developer Preview 3 includes the latest version of Android O platform with hundreds of bugfixes and optimizations. You can download the final API 26 SDK from the SDK Manager in Android Studio and Android Support Library 26.0.0 beta 2 from Google’s Maven repository and remember to update your project’s compileSdkVersion to API 26.
With this android developers should everything they need to test their apps on Android O (Here is the migration guide). If you already have an existing code using Android O preview APIs, you can check the diff report to see where your code might be affected. You can now also use Android Studio 2.3.3 from the stable channel to develop for Android O.
Last but not least, you can now publish APK updates compiling with, and optionally targeting, API 26 to your Google Play alpha, beta, or even production channels. Publishing O-targeted apps lets developers test the compatibility on existing devices and push updates to devices running API 26.