First things first, you’ll need the right software and hardware. You have to be running a Mac with OS X 10.8 or higher. You’ll need Apple’s IDE, Xcode and you’ll need iOS SDK. Xcode has a source editor, a graphical user interface, and other features that make it user friendly. The SDK has the tools, compilers and frameworks you need for iOS development.
Now that you have all the right software and hardware, you need to find a place to learn how to put it all together. The real truth is that app development is something that can be self-taught and all the tools to do it are right at your fingertips.
A simple Google search yields hundreds of websites that can explain you app development in a matter of weeks. Obviously someone with a coding or computer science background will be able to pick it up faster, but anyone with a desire to learn and the work ethic to stick with it can simply pick it up.
There are numerous websites out there that will teach you but some are better than the rest. Stanford University has an great web series on iTunes U that is completely free. This class needs some programming experience and a general programming background, but it is the cheapest and one of the best options available.