IRL: a tennis sensor you can use with any racquet | Engadget
Zepp Launches World's First 3D Tennis Swing Analysis For Mobile Devices | Business Wire
New Zepp Multi-Sport Training System—Now Available | Business Wire
Zepplabs | San Jose CA
Amazon.com: Customer reviews: Zepp Tennis 2 Swing & Match Analyzer
Zepp Tennis 2.0 Swing & Match Analyzer, Tennis Swing Auxiliary Products, Fitness Equipment for Men and Women, The Most Powerful Tennis Swing Analyzer, Track Parctice and Match Statistics : Amazon.se: Sports &