This particular app appears to need some seriously low level access to the phone. I can completely understand his frustration. However, with most general apps

This particular app appears to need some seriously low level access to the phone. I can completely understand his frustration. However, with most general apps, you can debug all your problems with a number of emulators (which all suck because they move twice as slow as the actual phones). Screen resolution differences are definitely a big challenge, then after that, the application's state. Someone can exit your app from the back button or the Home button, and then getting back in to a complicated app without a "Force Close" error can be a nightmare. Then you have to account for the fact that the phone is doing a number of other things at the same time as your app and it could get slowed down even more. When there is NO multitasking, you don't know how good you have it until you have it ;) Some days I dream of what it would be like to be an iPhone developer. No multitasking, one screen resolution. Ahh the life.