This app was mentioned in 1 comment, with an average of 5.00 upvotes
Hello,
I have written and released a real world app in Scala to test-drive it on Android : https://play.google.com/store/apps/details?id=com.alexd.carfinder
The app works well, but is not really popular due to the saturation of Carfinder apps ;)
I am using this great SBT plugin : https://github.com/pfn/android-sdk-plugin
The toolchain lacks a bit maturity (you sometimes have to fully recompile to avoid cache issue) and compilation can be slower than java due to proguard phase. However it is fully usable and getting better each released, and incremental compilation improve compilation time most of times.
Scala can make the Android API much easier and reliable to use and reuse, thanks to the functional programming and traits especially.
As mentioned in an other comment Functional Java + Bolts can be a good alternative for projects where using Scala is not possible, but you want some functional goodness.