How hard is it to learn Objective-C for iPhone Apps if you know C++, C and Python already? Is it better to use that rather than just C++ code when writing Apps? If so, why? I want to start iPhone Development and recently got an iMac for my Birthday. How long should it take me to be able to write iPhone Apps in Objective-C? Also, does the SDK cost money, and do you need an iPhone to develop Apps for it?