The Android mobile platform has exploded in popularity since it was released. Android has become a major competitor to iPhone, with no end in sight. Unfortunately, to take advantage of the platform you needed to know Java…until now. JRuby works unmodified on Android, and so as part of the 2010 Ruby Summer of Code, we’ve started to put together a framework and generators for building Android apps entirely in Ruby. You can generate a new app, make your minor changes (or your full application), and then run a rake task to build the app itself. It’s the easiest way yet to build an Android application! This talk shows the basics, from generating an app to using various Android libraries.