iOS users continue to purchase more apps, and pay for more expensive apps, than their Android counterparts, despite the gulf in overall sales and user figures:
http://blog.flurry.com/bid/85911/App-Developers-Signal-Apple... "Running a comparison of revenue generated by top apps on both iOS and Android, Flurry calculates that the difference in revenue generated per active user is still 4 times greater on iOS than Android. For every $1.00 a developer earns on iOS, he can expect to earn about $0.24 on Android. These results mirror earlier findings from similar analysis Flurry conducted in Q4 of 2011 and Q1 of 2012."
OP remarked that iOS is no longer the major market for app store developers, implying that some other mobile platform is. If not Android, what else would it be?
http://www.distimo.com/blog/2011_12_distimo-releases-full-ye...
In 2011 iPad app revenues alone topped Android Market revenues by a significant margin.
edit: some more recent sources: http://www.appannie.com/game-of-phones/
http://blog.flurry.com/bid/85911/App-Developers-Signal-Apple... "Running a comparison of revenue generated by top apps on both iOS and Android, Flurry calculates that the difference in revenue generated per active user is still 4 times greater on iOS than Android. For every $1.00 a developer earns on iOS, he can expect to earn about $0.24 on Android. These results mirror earlier findings from similar analysis Flurry conducted in Q4 of 2011 and Q1 of 2012."