I create my own custom timers (or find someone has already done so) using http://www.intervaltimer.com/. Sometimes I make them specific enough to do a workout without the referring to the pictures http://www.intervaltimer.com/timers/9383095-cardio-go-1 and sometimes I use a generic timer on a background tab while looking at the workout http://www.intervaltimer.com/timers/...-circuit-timer. I like to start the timer and not have to fuss with it between sets or exercises and not have to track sets. Doing a search for darebee, http://www.intervaltimer.com/search/?q=darebee&page=1, on the site, it appears many other bees also use it and sometimes I use one already there. A timer that can be set to repeat the same interval over and over would be useful here though.

In a perfect world, it's a good candidate for a custom timer, but I realize I'm already creating work and I have no idea how hard that is to set up.