Windows Mobile phones sold more last quarter than the number of iPhones (any kind) in existence. Blackberry represents more than half of the corporate phone market.

Windows Mobile (now Windows Phone) applications have a higher price point b/c people who buy those phones can and are willingly to pay. Blackberry applications have an even higher price point.

Of course, you'd have to be willing to target international users for WinMo, and business apps for BlackBerry, but at least you're not stuck with customers who probably aren't old enough to drink.