Toma Timer Plus is your standard 3 in 1 timer, stopwatch, and alarm setting application.
The timer tab allows you to set up to 2 timers that rotate (Pomodoro timer) for optimal studying efficiency. If you choose to use the Pomodoro timer in the background (i.e. use a different app), the timer notifications will stop after 20 rotations in order to save memory on your device.
The stopwatch and alarm tabs are also included for your convenience.