This app will let you perform sets with a pre fixed tut more easily by counting reps and seconds in each phase of the contraction for you. It will do it both with the change of the color and the change of the sound. Brown = Eccentric, Red = Isometric, Green = Concentric. Set some seconds pre set to position before the set and the app will let you know when to start. If you set all seconds to 0, you will have 2 seconds to perform each rep. Good Workout