[on_and_off]

Kotlin has been supporting Android for a while, with the promise that the language takes Android's needs into account. For example to do not request JVM 8 as a minimum...

Kotlin has been unofficially supported already by the Android tools team for some time. Meaning that they would work with the kotlin team in order to make sure that when a tools update breaks the kotlin build tools, they can be fixed in a timely manner.

Now that it is officially supported, we might have : - idiomatic android api for kotlin (there is already 100% interop, but sometimes java's code can be better expressed in kotlin) - official android documentation in kotlin. - I guess that kotlin will focus even more on Android's support

It is not going to change anything regarding kotlin compatibility with Android. Since kotlin outputs bytecode, it would be almost impossible for Android to permanently break kotlin compatibility without also breaking 99% of all Android's libs.