title: Smooth scrolling with inertia and edge resistance/snapback
body: <p>I implemented basic scrolling via touch dragging and multitouch zooming for a custom view. This works well, but now I'd like to add some advanced features.</p>
  
  <p>For example, in the Google Maps application, when you drag around the screen, after you stop dragging it will still continue to move a bit (inertia). And some browsers (e.g. IPad Safari) allow you to drag the screen further than the visible area of the website, but then the screen will quickly snap back to the edge of the website.</p>
  
  <p>I'd now like to implement something similar, but to do that I need to change the active screen region <em>after</em> the touch events happened in regular intervals to perform the animation. How can I do that?</p>