title: Photo viewer (with zoom, pan, scale etc)? Alternative to Three20
body: <p>I have an app with a few pictures. If the user clicks on one of them, I want him to be able to zoom, pan, scale and so on. I don't need something like Three20. First of all, I'm loading the images from file inside the app, second I don't need the "library" feature (that displays all the images in a grid > like the Photos.app). So I only need the part in the <strong>left</strong> picture... </p>
  
  <p><img src="https://i.stack.imgur.com/e3Uja.png" alt="enter image description here"></p>
  
  <p>How can I do that? Is there any "sample class" or tutorial?</p>
  
  <p>Thanks a lot in advance!</p>