An easy to use widget which keeps track of how much time you spend walking or running per day by using the phones sensors.
It can also be used as pedometer to count your steps and/or record your walking route with GPS.
Try the free version to get an impression of this app. This full version has more features and no adds.
Short Instructions:
Download and install the App. To set a widget go to your homescreen, press the menu key, select widget and then TimeWalker. Once the widget is set the walk detection will be active all the time. To disable it click on the foot icon of the widget - it will get crossed out to show that the detection has stopped.
Because Time Walker detects walking by monitoring the phones sensors and search for walk patterns, you should put the phone in a pocket near your waist for best results.