Developing for Nintendo requires and office as far as I know that's always been the case. Developing for iPhone requires previously published work through some other channel and also that you don't step on Apple or AT&T's toes. As Dreamora said, there are multiple duplicate game types up there and they don't care. If you're making a game and have previously published work then developing for iPhone is pretty to get approved for. It's not as open as the PC ... but it's not as locked down as the consoles.