Health
Counts your steps with the phone's motion sensor and draws your walk live on the map: distance, time, pace and calories. Your walks are saved to your account.
Keep this page open while you walk. The screen stays on while the walk is running. Phone browsers stop GPS and the motion sensor when the screen is off or you switch apps, so the steps and route pause until you come back.
Height sets your step length (used when the phone has no motion sensor). Weight is used for calories. Calories are an estimate.