Interestingly, a majority of that cash (91% for both iOS and Android) stems from microtransactions inside the game, not purchasing titles outright. Besides user demographics, Newzoo CEO Peter Warman says there's one difference between iOS and Android that could explain the revenue discrepancy: Apple requires users to link credit card information to their accounts. "I can hardly imagine any other company in the world that would be able to get away with this, including Google and Microsoft," Warman said.
Source: Techspot