The basic issue here is that in the US, iphone is only available with 1 carrier - AT&T -- which has only 30% or less of the wireless customers in the country. Since the reach is so low, iphone has to have a low market share. Once it is available with all carriers in the US, then it will be an even playing field. Even then ofcourse, it will have to compete against 20+ android phones, atleast it will have the opportunity to. In Europe, where iphone is generally available with more than 1 carrier, it's rate of getting new subscribers is still 3 times android! See:

http://www.clickz.com/clickz/stats/1733041/apple-google-cont...