Add the following entries to your .gitignore if you're using IDEA IntelliJ for Android development.
Since the ignore list will ignore jar files, you'll need to use git add -f if you need to add any lib's in the form of jar files.
# IDEA Ignores
# Generic Android ignores
It's also published at the awesome site gitignore; http://gitignore.com/posts/idea-android-development/