Considering the recent success of the iPad and iPhone 4, that might not happen at all or be in the far future. On the other hand, the iPhone market might be mor

Considering the recent success of the iPad and iPhone 4, that might not happen at all or be in the far future. On the other hand, the iPhone market might be more saturated for the kind of applications you want to make. Still, once you got the idea, the graphics and the general structure, porting apps either way isn't that hard, even if you have to rewrite the code, so investing in a used Mac Mini + iPod Touch might be worth it in the end.