ReadWriteWeb has an article today trying to explain how iOS usage is so much higher than Android usage despite Android having a much larger install base. The article speculates but to me the reason is clear.
It’s because iDevices are more expensive. Only more dedicated users are willing to pay the premium. Marginal users are more likely to buy the cheaprer hardware. They’re the users for whom a $200 tablet is worth it but a $600 one is out of the question. They’re the users who are more likely to let that unsatisfying slow resistive touch-screened no-name device gather dust. If you drop half a grand on an iPad you don’t ignore it.
As for apps downloads and sales, Android, by its philosophy, tends to attract more technical users for whom it would be a personal failing to pay for something when they could get for free.
It’s like going to a prostitute. Why should I pay, when if I apply myself, maybe I could get it for free? -George Costanza, Seinfeld
Android users are the Georges of mobile users. Therefore they spend less on apps. Therefore developers that are chasing dollars develop for iOS.