Really good app with one flaw

I have used this app for at least 2 years in my fitness classes to keep track of time during tabata, HIIT, AMRAP and circuit workouts. I have also used it when doing interval training while Im running. The one thing that really bothers me is that I cannot play my music on my iPhone at the same time as I use this app. If this glitch were fixed, then I would give it 5 stars.

Sjrs88 about Simple Interval Timer, v1.4