Decent workout, but buggy app – Seven: 7 Minute Workout Review

I started using Seven because my wife was using it, and it's a good way to burn some calories without to much of a time investment. My main complaint is that it randomly crashes on my iPhone 6, losing my workout progress. This happens ~10% of the time I use it, which is just enough to be really aggravating, but not enough to give up and delete it.
Review by DJ Argon on Seven: 7 Minute Workout.