diff --git a/samples/tracker.html b/samples/tracker.html
index 5dca272..f2da0f9 100644
--- a/samples/tracker.html
+++ b/samples/tracker.html
@@ -41,8 +41,8 @@
 	var i, len = touches.length;
 	for (i=0; i<len; i++) {
 		var touch = touches[i];
-    var px = touch.pageX;
-    var py = touch.pageY;
+		var px = touch.pageX;
+		var py = touch.pageY;
 
 		ctx.beginPath();
 		ctx.arc(px, py, 20, 0, 2*Math.PI, true);
@@ -53,7 +53,7 @@
 		ctx.lineWidth = 2.0;
 		ctx.strokeStyle = "rgba(0, 0, 200, 0.8)";
 		ctx.stroke();
-    console.log('drawn circle at ' + px +',' + py);
+		console.log('drawn circle at ' + px +',' + py);
 	}
 
 	updateStarted = false;
@@ -64,18 +64,23 @@
 	ctx = canvas.getContext('2d');
 	timer = setInterval(update, 15);
 
-canvas.addEventListener('touchend', function() {
-	ctx.clearRect(0, 0, w, h);
-});
-
-canvas.addEventListener('touchmove', function(event) {
-  event.preventDefault();
-  touches = event.touches;
-});
-
-canvas.addEventListener('touchstart', function(event) {
-  console.log('start');
-});
+	canvas.addEventListener('touchend', function() {
+		event.preventDefault();
+		ctx.clearRect(0, 0, w, h);
+		touches = [];
+	});
+
+	canvas.addEventListener('touchmove', function(event) {
+		event.preventDefault();
+		touches = event.touches;
+	});
+
+	canvas.addEventListener('touchstart', function(event) {
+		event.preventDefault();
+		touches = event.touches;
+		console.log('start');
+		  
+	});
 };
 
 </script>