One of the key ideas of Groovy is to help Java developers be more productive, so why not bring it to Android? Luckily, Cédric Champeau has done exactly that with this Gradle plug-in on available on GitHub.
It looks pretty straight-forward: edit your build.gradle a bit, choose your Groovy version and modules, add a depedency, and that’s about it. It does seem to be leaning toward Android Studio, but that’s okay, people seem to like Android Studio.