MOBO is a free App which runs on Android, Apple, Nokia and Windows phones. Here’s the MOBO web site.
The courses at Burrs Country Park, along with its Activity Centre, have been set up with MOBO controls, so if you download the app, choose yourself a name, and select a Burrs course, the map and control descriptions are placed on your phone and you can use them whenever you want. At each control (including the Start/Finish), there is a plaque with a unique QR code – when you reach the control, you touch the app’s camera icon and scan the QR code. The control code and current time are saved, and will be uploaded to the MOBO web site, so that your activity is recorded and you can see what other people have done. Here’s a little document to help get you going – MOBO_Getting_Started_Guide.