title: How to draw a small image on Top of Larger Image by press and clear by Touch
body: <p>Wanted to create a fun app with photo. This is the scenario:</p>
  
  <ol>
  <li>I have a photo of size 640X 480 in the page ( as the background)</li>
  <li>Display Thumbnail pn the left-side 100x100</li>
  </ol>
  
  <p>This are the problems I wanted to solve:</p>
  
  <ol>
  <li>User select a Thumbnail photo 100x100 on the left-side</li>
  <li>User press or click any where in the large photo ( 640x 480), after pressing, it draws the Thumbnail. What format to use Png or Jpg for Thumbnail so that when you draw it, the background of the Thumbnail will be transparent.</li>
  <li>user can clear the Thumbnail by touching the Thumbnail.</li>
  </ol>