Kotlin and Java are from different era's, Java's one of the most verbose and limited modern typed languages for functional programming whilst Kotlin's one of th

Kotlin and Java are from different era's, Java's one of the most verbose and limited modern typed languages for functional programming whilst Kotlin's one of the best and both have great tooling support for developing Android Apps courtesy of JetBrain's tooling prowess, where to enable Kotlin support in Android Studio you just need to enable the Kotlin plugin: https://kotlinlang.org/docs/tutorials/kotlin-android.html https://kotlinlang.org/docs/tutorials/kotlin-android.html And configure your project to support Kotlin with a find action or a `Tools > Kotlin > Configure in Project` Menu item click. From there you can mix and match Java and Kotlin classes in the same project with great interoperability for calling code between each. The Kotlin plugin also has a nice feature (Ctrl + Alt + Shift + K) to convert a Java class into idiomatic Kotlin which is a great way to explore Kotlin features. Even whilst the plugin has stability issues, I don't see myself developing another Android App with vanilla Java 7 - Kotlin's just so much a more productive and enjoyable dev experience, that Android Studio should have the Kotlin plugin enabled by default.