title: Overlay UIImageViews with Multiply blend mode?
body: <p>I have 2 UIImageViews that are shown on top of each other. One of them can be dragged around using a Gesture Recognizer. </p>
  
  <p>Is there a way that the ImageViews can be rendered using a blend mode like Multiply? Such that when they move on top of each, they get rendered with that blend mode?</p>