Develop on Android or iPhone?
cesare: >Update: I should add that the two biggest deciding points for me are development enjoyment and speed of development.This is subjective. Try both of them for a while.If you need to decide first to buy the hardware keep in mind that the iPod Touch ($229) is essentially an iPhone without the phone/gps capabilities. So you can use it for testing if  you're not going to use the phone functionalities.You have to add $100 (it's a yearly fee) to apply to the developer program in order to upload your code on the device and to make your app available (even if for free).The iPhone developement tools are pretty good, too. Haven't tried to develop on Android, yet.