jquery.nodoubletapzoom.js

// jQuery no-double-tap-zoom plugin

// Triple-licensed: Public Domain, MIT and WTFPL license - share and enjoy!

(function($) {
  var IS_IOS = /iphone|ipad/i.test(navigator.userAgent);
  $.fn.nodoubletapzoom = function() {
    if (IS_IOS)
      $(this).bind('touchstart', function preventZoom(e) {
        var t2 = e.timeStamp
          , t1 = $(this).data('lastTouch') || t2
          , dt = t2 - t1
          , fingers = e.originalEvent.touches.length;
        $(this).data('lastTouch', t2);
        if (!dt || dt > 500 || fingers > 1) return; // not double-tap

        e.preventDefault(); // double tap - prevent the zoom
        // also synthesize click events we just swallowed up
        $(this).trigger('click').trigger('click');
      });
  };
})(jQuery);