The Walk-A-Cise mobile phone application has been developed to help patients with peripheral arterial disease. Feedback from many patients shows that they find it difficult to know how far they are able to walk. Most patients do not have access to a supervised exercise class, and do not have the time to travel to the hospital for classes. The Walk-A-Cise App enables patients to exercise at their own convenience, in their own space at their own time. By seeing results every day patients know that they are walking further, and if linked to their hospital, knowing that healthcare professionals can see the results gives security that they are being monitored. The App is simple to use. A button is pressed to start a walk, and the same button to stop, with distance measured by GPS tracking. This is then automatically saved. Patients can also see previous walks so they can see how they are improving.