Ok, having sold apps on both Android and iOS platforms I can tell you with 100% certainty that the same app will have sales that are an order of magnitude large

Ok, having sold apps on both Android and iOS platforms I can tell you with 100% certainty that the same app will have sales that are an order of magnitude larger on iOS than they will on Android. Android users don't like paying for things as much as iPhone users do. Yes, Angry Birds makes a lot with ads, but they still made more on iOS. I think they had made something like $10 million on iOS before they made $1 on Android. So, yeah go and do Android dev, but you will easily make 5-10x as many sales with the same app on the iTunes app store. Build and app for both and try it. Also, if your app doesn't suck you can make way more selling the app than giving it away. I tested ads and they don't make nearly as much as paid downloads do. Now, I didn't have a top 100 app, so maybe if you have a big hit ad-supported stuff is good money, but if you have a top 100 app you should be making great money either way. I think the one place where there is a good chance of making money in Android land is to do android specific features that the OS should have had in the first place. Like, better UI/widget stuff, better keyboards, and so on. Things that can only be done on android.