Meet "Vi," the Siri of fitness
What makes Vi different from a Fitbit, Pebble, Apple Watch, and every other wearable you've seen is that it's actually like having a personal trainer, only instead of a real person shouting in your ear, you get instructions and feedback from an interactive AI that goes by the name of Vi -- basically, a more enthusiastic, human-like, hardass version of Siri. The device itself resembles a pair of wireless earbuds, tethered to a U-shaped neckband. Those earbuds are capable of a lot more than just pumping out workout jams (although, side note, they were developed with audio pros Harman/Kardon). They have aerospace-grade biosensors that constantly monitor your heart rate, speed, and level of exertion while simultaneously tracking environmental factors like elevation, location, and weather.