 <p>In the ZBar sdk, ZBarReaderView has a method called "TrackingColor". The default is green. Here is the code to change the tracking color:</p> <pre><code>reader.trackingColor = [UIColor redColor]; </code></pre> <p>I am using a TabBar. So here is the code I used to get it to work:</p> <pre><code>ZBarReaderViewController *reader = [tabBarController.viewControllers objectAtIndex: 0]; reader.readerDelegate = self; reader.readerView.trackingColor = [UIColor redColor]; </code></pre> <p>I hope this helps!</p>