Pass on touch events to the UIView \ UIButton underneath your current view if your pixel alpha channel is 0 (if the pixel is transparent)
Useful if you don't want to catch all touch events on UIViews \ UIButtons with a non squareish appearance.
A simple way to add dynamic RGB color sliders to an iOS application. When the value of one slider changes, the background colors of the others change accordingly. For a full description, check out the README on github.