Developing iOS apps is pretty creative and interesting task, and easy to start with, given the fact that you know basic programming concpets and can code comfortably in C/C++.
Though pre-requisites include A Mac :p and Xcode , but if you have crossed the barrier then its pretty easy and amazing to start with.
If you are starting with iOS development, following this guide will help you get acquainted with iOS technologies quickly ,with good understanding of underlying concepts.
Always use Latest Xcode and Latest iTunes
Read and work along this tutorial quickly ......