Yup, it does narrow your market even further. But not in a very meaningful way. iPhone owners are drastically more likely to download and use your app than on a

Yup, it does narrow your market even further. But not in a very meaningful way. iPhone owners are drastically more likely to download and use your app than on any other platform. The hard question is whether to launch on the web or mobile first. Once you've decided on mobile first, choosing iPhone first is a fairly obvious choice.