To get started with Kotlin, download the Android Studio 3.0 preview, open one of your existing Java files, and then choose “Convert Java File to Kotlin File” in the Code menu.

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.

To learn Kotlin for Android development, you’ll first need to download Android Studio and set everything up. See also: How to install Android Studio and start your very first project ...