title: Changing touch event source on Mobile Safari
body: <p>I have two overlapping images. I touch the topmost image and start moving (<code>touchmove</code>) finger around. All subsequent <code>touchmove</code> events are received by that image. In the middle of this interaction I want the events to go to the image underneath, so that I can move it around instead.</p>
  
  <p>How to change the event source to the image underneath? That is, once an object has started receiving touch events, how do I change the target of those events?</p>