Some of the best apps are those that do one simple thing well, and Bit Timer for iOS looks like it will provide that for workouts. Released last week, the $0.99 app lets users set intervals by moving a large color-coded slider up and down, instead of using the default iOS selection wheel or typing to set a time. The home screen includes three sliders for work time, rest time, and number of repetitions; to set up a workout, you just need to tap each one, move its slider up or down, and press a button to start.

There's not a lot to this app, but the attractive design and details help it earn its dollar. A ten-second countdown will help you get in place before starting intervals, and it auto-fades any music you're playing to let you hear the the chimes that mark your status. The work times go from five seconds to two minutes and the rest times from zero to two minutes, so you won't be using this for anything that requires extended periods of either. It also doesn't appear to save custom workouts, though it shouldn't take long to change the times. Bit Timer is supported on both iPhones and iPads running iOS 4.3 or later.