Astonishingly accurate pulse measurement. Strap can be worn anywhere on the body. App can track your distance, speed and pace using your iPhone’s GPS. Easily access your stats from a device that you most likely already own. Real-time feedback spurs you...

If you’re going to schlep your iPhone anyway, why wouldn’t you just buy a dedicated training device? Expensive for a heart-rate monitor. App is difficult to use. Turns out checking the mail only burns 15 calories… Bummer