Interval App Timer Needs Finer Adjustments

The current times available jump from 2 min to 5 min to 10 min

This makes progression for HIIT style training difficult, when attempting to add 10 sec to a work interval, or take 10 sec away from a rest interval.

For example, 2:10 sec Work, 4:50 sec rest, etc.

Currently, the only solution is to write the workout as a regular style workout, and have the clients download and use a separate interval timer app, which takes away from the "custom app" experience