Bevan is correct - unfortunately the numbers don't add up for Android to (a) break even and (b) make back some beer money for the many (hundreds/thousands) of hours it would take to do it.
Whilst I have made some beer money from the iPhone app (I get about $4 per copy sold), I worked out that I would have been better off flipping burgers at McDonalds for time invested. And the iPhone market is pretty big. However this doesn't worry me as I love doing it as a hobby/side business to work.
Unfortunately unless you're making an app that millions of people around the world will buy, it's got to be botique & expensive to make it as a successful business.