The samples obviously use gradle. I normally use sbt to build my apps, but this time I decided to stick with gradle, because I wanted to make it easy for people to consume the code (and embracing a new build system might be too big of a step as a first step). It also gave me an opportunity to checkout the gradle-android-scala-plugin.
I also enhanced the gradle-ensime plugin to make sure it generates a valid .ensime file for Android projects.
Now I have a working structure in place. If you want to help with the porting effort, please create an issue to let everybody know that you want to port on of the samples, fork the repo and send me a pull-request to get your port into the repo.