Zepp's 3D motion sensor helps you get better at golf, baseball, or tennis. The Zepp sensor will probably be pretty useful for people that take their training seriously. The device can attach to a racket, bat or a glove and will collect data from the swings you take and show you on your smartphone through Bluetooth.
Zepp can tell you stuff like the speed and power, angles, hip rotation from your swings, and even your shot type for tennis. Zepp's 3D motion sensors are now available from zepp for $150 or from Apple and Verizon on the 19th. The device comes with the sensor, app, and the mount.