That’s important because if you want to target Android O, create an Instant App, start developing with Kotlin, or use the latest Android app performance tools, you’ll need Android Studio 3.0.

Google's Android Studio 3.0 dev environment has just become available in the stable channel, with built-in support for Kotlin and Java 8.

Google also today announced that it is making Kotlin a first-class language for writing Android apps. This first preview of Android Studio 3.0 already includes full support for this new language.