Stop scratching when the mouse is moved outside of the scratchable area

package.json

@@ -1,7 +1,7 @@
 {
   "name": "wScratchPad",
   "title": "wScratchPad jQuery Plugin",
-  "version": "2.1.0",
+  "version": "2.1.0-dev",
   "description": "A jQuery plugin to mimic a scratch card or pad behaviour.  Allowing you to scratch off an overlay as either a color or image.",
   "main": "wScratchPad.js",
   "repository": {

src/wScratchPad.js

@@ -39,7 +39,7 @@
 
       // Setup event handlers.
       this.$scratchpad
-      .mousedown($.proxy(function (e) {
+      .on('mousedown', $.proxy(function (e) {
 
         // If disabled we just return true which menas
         // our our this.scratch will remain as false.
@@ -52,12 +52,21 @@
         this.scratch = true;
         this._scratchFunc(e, 'Down');
       }, this))
-      .mousemove($.proxy(function (e) {
+      .on('mousemove', $.proxy(function (e) {
         if (this.scratch) {
           this._scratchFunc(e, 'Move');
         }
       }, this))
-      .mouseup($.proxy(function (e) {
+      .on('mouseup', $.proxy(function (e) {
+        if (this.scratch) {
+          this.scratch = false;
+          this._scratchFunc(e, 'Up');
+        }
+      }, this));
+
+	  // Catch mouseup outside of image or outside of window
+	  // (might not fire in all browsers)
+	  $(document).on('mouseup', $.proxy(function (e) {
         if (this.scratch) {
           this.scratch = false;
           this._scratchFunc(e, 'Up');
@@ -122,7 +131,7 @@
           $(new Image())
           .attr('crossOrigin', '')
           .attr('src', this.options.fg)
-          .load(function () {
+          .on('load', function () {
             _this.ctx.drawImage(this, 0, 0, width, height);
             _this.$img.show();
           });
@@ -212,11 +221,17 @@
       //start the path for a drag
       this.ctx.beginPath();
       this.ctx.moveTo(e.pageX, e.pageY);
+
+      // force redraw to fix android browser bug
+      this.canvas.style.zIndex++;
     },
 
     _scratchMove: function (e) {
       this.ctx.lineTo(e.pageX, e.pageY);
       this.ctx.stroke();
+
+      // force redraw to fix android browser bug
+      this.canvas.style.zIndex++;
     },
 
     _scratchUp: function () {