Pacemaker is a simple but powerful app for joggers of all levels from novice to experienced marathon runner. It uses your phone's GPS to monitor your speed and gives you voice feedback to keep you moving at your target speed. Experienced runners can use Pacemaker to monitor and record their workouts and it is especially useful for those who want to increase their performance. For novice joggers, or those wanting to start jogging, the three phase walk-jog-run interval training program is the easi