I don't see the compelling reason to start with Android in the free-app-as-front-end-to-web-service case. Is it because Android phones (briefly) outsold iPhones? Last I heard, iOS still has something like a 60% lead in install base, and the latest data says iPhone sales are outpacing Android phone sales again.
iPhone sales don't outpace Android. Android has a 50% market share in new sales last quarter in US, and iPhones have I believe 28-29%. The news was that Android dropped from 53% to 50% when the Verizon iPhone was launched, not about iPhones outpacing Android in market share.
They tried to make a big deal out of it, trying to show that it could be a downward trend, but it's nonsense. Android sales keep growing worldwide, and I'm sure it will rise above 50% in US by the time iPhone 5 launches (and take a hit again for a few months, and then rise again).
