This basic version of the Fitbit fitness tracker won't tell you how well you've slept, and can't track your performance on a Stairmaster. But if you just need a device that will track your steps and calories burned, and can sync wirelessly with Fitbit's website and smartphone apps, the Zip is a good choice at a great price. If you want something more advanced, consider the gdgt Must-have Fitbit Ultra -- or wait for the Fitbit One, due out next month.