• http://redartisan.com/2011/05/13/porting-iconapp-core-graphics
• http://cocoawithlove.com/2011/01/advanced-drawing-using-appkit.html

IconApp is a port of an AppKit example app written by Matt Gallagher demonstrating complex drawing using AppKit classes such as NSGradient, NSBezierPath, etc.

This version of IconApp works under iOS and uses Core Graphics to draw the same shape. Please see the various links above for more information.