A UIScrollView subclass that shows previews of the pages on the left and right. It uses a delegate much in the way UITableView uses a data source. This is largely based on WWDC 2010 session 104 and the PhotoScroller sample, without the CATiledLayer pinch-to-zoom stuff.
MHRotaryKnob is a UIControl that acts like a rotary knob. In operation it is similar to a UISlider but its shape is square rather than long and narrow. Great for music apps where you can use it as a volume or panning control. You can easily customize the look of the control using your own images.