I have been using this for a couple months now. I use it about 3 times a week. The workouts are good. I like how they build up the intensity over time. I, too, have bumped the screen and the workout started over again. I run on the treadmill and Im not sure if it would work well running outside. Im sure I would hit the screen more often. The music seems to work fine for me. I like that I get to choose my own songs. Overall, I like the app and I would recommend it to others.
Javadoggy about Couch To 5K - Run, Jog, Walk