[jamesbkel]

Somewhat in the same vein... a friend of mine teaches ESL classes for foreign US university students. He made a pretty basic app - it's not polished but it's perfectly functional - to help his students study vocab/tenses/etc. I forget now if it was free or $0.99, either way he didn't actually have that many downloads since it was only designed for his class.

That said, the students loved it. And, he could also update the app as the course went along. Finally, although he only made enough through App Store sales to maybe go out for a nice meal, it translated into promotions, bonuses and the like. So ultimately, it paid off.

My main point is: in addition to selling niche apps at a premium, there's also the opportunity to develop cheap/free apps that otherwise help you move ahead within a niche market.