===================================================================
--- original.js
+++ change.js
@@ -31,12 +31,23 @@
 		enemy.x = Math.random() * 2048;
 		enemy.y = Math.random() * 2732;
 		enemies.push(enemy);
 	}
+	var touchStart = {
+		x: 0,
+		y: 0
+	};
+	var touchEnd = {
+		x: 0,
+		y: 0
+	};
 	stage.on('down', function (obj) {
-		var pos = obj.event.getLocalPosition(self);
-		var dx = pos.x - hero.x;
-		var dy = pos.y - hero.y;
+		touchStart = obj.event.getLocalPosition(self);
+	});
+	stage.on('up', function (obj) {
+		touchEnd = obj.event.getLocalPosition(self);
+		var dx = touchEnd.x - touchStart.x;
+		var dy = touchEnd.y - touchStart.y;
 		var distance = Math.sqrt(dx * dx + dy * dy);
 		hero.move(dx / distance, dy / distance);
 	});
 	LK.on('tick', function () {