I have considerable experience in making Android applications. For my new project, we have decided to do Test Driven Development (TDD). I have been getting my hands wet on Robot
For off-device testing, look at Robolectric
For on-device testing, look at Borachio
Bottom line: it's still very, very difficult to do well. Things are improving (the situation is dramatically better today than it was 6 months ago) but Android is comfortably the most test-hostile environment I've ever written programs for.