90% of the money spent on apps is spent on iOS apps

"Apple devices still hammering the rest when it comes to real spending by punters.
Analyst Gene Munster with Piper Jaffray made his projection earlier this week, and also said that he believes Android Market has generated a miserly seven per cent of the amount Apple's App Store has grossed in its lifetime.
He also claims that about $330 million has been generated on the Android Market, and that only 1.3 per cent of the apps on it are paid.
Munster doesn't see Android making up too much ground in revenues despite the gains its making in overall usage."

Source:  MobileEntertainment, 22nd November 2011