title: Double-tap zoom & hammer.js issue
body: <p>Please could someone advise me on the following:</p>
  
  <p>I have an image that when double-tapped or pinched-out should display an overlay.</p>
  
  <p>I have used hammer.js which successfully carried out the pinch-out showing the overlay.
  I have used double-tap in hammer.js to trigger the overlay however this does not work because the native iOS double-tap to zoom occurs. So instead of showing the overlay it zooms into the image I tapped on.</p>
  
  <p>Does anyone know how I can stop this issue on the image so I can get hammer.js to open the overlay?</p>