Fix for touch devices - only works if page is has no scrolling. I've tested it no iPad with iOS 6.01.

src/util/dom_event.js

@@ -189,30 +189,20 @@
     }
 
     return {
-        x: event.clientX + scrollLeft,
-        y: event.clientY + scrollTop
+        x: pointerX(event) + scrollLeft,
+        y: pointerY(event) + scrollTop
     };
   }
 
   var pointerX = function(event) {
-    var docElement = fabric.document.documentElement,
-        body = fabric.document.body || { scrollLeft: 0 };
-
     // looks like in IE (<9) clientX at certain point (apparently when mouseup fires on VML element)
     // is represented as COM object, with all the consequences, like "unknown" type and error on [[Get]]
     // need to investigate later
-    return event.pageX || ((typeof event.clientX !== 'unknown' ? event.clientX : 0) +
-      (docElement.scrollLeft || body.scrollLeft) -
-      (docElement.clientLeft || 0));
+    return (typeof event.clientX !== 'unknown' ? event.clientX : 0);
   };
 
   var pointerY = function(event) {
-    var docElement = fabric.document.documentElement,
-        body = fabric.document.body || { scrollTop: 0 };
-
-    return event.pageY || ((typeof event.clientY !== 'unknown' ? event.clientY : 0) +
-       (docElement.scrollTop || body.scrollTop) -
-       (docElement.clientTop || 0));
+    return (typeof event.clientY !== 'unknown' ? event.clientY : 0);
   };
 
   if (fabric.isTouchSupported) {