<a href="http://jakewharton.com/the-android-build-system-is-broken/">Broken Android Build System</a>
I believe this applies to Java itself not just Android.
Anyone know of a good build system? Leave it in the comments, PLEASE
We use maven for all of our Android projects and it works like a charm. There are multiple build system for Java as you may already know.
For Android in particular this plugin works great for both Apps and APKLibs.
These are also very handy archetypes for different project layouts including ones with integration tests.
Since Android Studio uses Gradle I believe it's a best choice.