How to make custom buttons in iOS?

Question

The default iOS UI is nice but if I wanted to use images for buttons instead how would I do that - is it OpenGL?

Answer 1

You can simply use PNG files that you create yourself. The UIButton class allows you to use custom images for all the different states of the application.

You don't really need to do custom rendering yourself, but if you really want, you can use UIKit to draw the images yourself in code (no OpenGL involved): http://developer.apple.com/library/ios/#documentation/2ddrawing/conceptual/drawingprintingios/graphicsdrawingoverview/graphicsdrawingoverview.html