If you want to do push-up to fitness, then "Push-up auto counter" will be helpful to you. When you do push-ups, just open the program and put iPhone bottom of your head, then you approach to iPhone, the program can do to help you record the number and the time spent.
Push-ups auto counter has two modes, one is the "standard mode" is not limited to time, do until you want to stop. The other is the "time mode", timing one minute, to see how much you can do.
The record of the results, you can "score" to confirm. "Achievements" were recorded in "standard mode" and "time mode" results.

I wish you have a healthy body! !