Last year we saw a lot of fitness gadgets start to gain popularity. Fitbit, Nike's Fuelband and Jawbone UP were among the more popular entrants. This year at CES we saw an absolute explosion of activity trackers, with every company you can think of introducing their own version. LG, Sony, Garmin, and Razer were just a few of the many to talk about. One of our favorites this year came from a company we'd never before. Reign by Jaybird stood out among the field by offering automatic activity recognition, as well as sleep recommendations based on how active or not you were that day and how much sleep you typically need.