Constantly Freezes iPhone

I was very happy with this bare bones app for tracking my workouts for about 6 months. Then as of about 3 weeks ago it started freezing on me in the middle of my times workouts. It causes all apps and functions on the iPhone to stall. I wrote to the developer last week and have received ZERO response or feedback. Im giving them until this weekend to fix the issue or contact me. There are several other free apps that I can convert to that are rated much better than this if not. I would not purchase until they address this issue.

Docbeefaz about PUMPING WEIGHT