OBGradientView is a simple UIView wrapper for CAGradientLayer. It is a plain UIView whose layer is a CAGradientLayer. It is useful if using a view is more convenient than using a layer, e.g. because you want to use autoresizing masks.
OBShapedButton is a UIButton subclass optimized for non-rectangular button shapes. Instances of OBShapedButton respond to touches only in areas where the image that is assigned to the button for UIControlStateNormal is non-transparent.