One of the biggest problems with the mobile (smartphone) market is the tremendous challenge with support and testing. This chart shows how Android phones tend to (not) be updated. Windows mobile devices aren't shown, but my personal experience with Windows mobile devices in the past put them a lot closer to Android than iOS in terms of device updates. This is a big problem for support, development, and testing. Unless you can afford to support this kind of fragmented market, for most organizations a mobile web app is a much better, easier to support & test investment. This doesn't mean giving up on app stores - technologies such as PhoneGap still let you build for them, as well as leverage native capabilities such as location awareness, off-line use, and more.