Prototype of  Challenger Challenger graph

Demand for fitness wearables is exploding but they don’t meet the needs of athletes today. For actual improvement, they need instruction and motivation tailored to their sports, not an overload of data. Shot Stats gives athletes actionable and qualitative feedback with a training service powered by integrated hardware and software. Our vision is for tennis to lead the charge into this new era of powerful data-driven athletic insight. The revolution begins with Challenger, which provides instant data and audible cues while on the tennis court. Our future products include Challenger Lite and Flex. Lite will be smaller and less expensive than Challenger, without a screen, to appeal to recreational players. With Flex, our all purpose device, we will spread to new sports. Flex is versatile and will attach directly to you, your clothes, and your equipment. Using data from one or more of those devices, our app will create personalized lesson plans to drive and track your improvement.

Employees: 5


Your racket. Your swing. Your game.

Challenger, from Atlanta-based HAXLR8R graduate Shot Stats, is a small device that attaches to any tennis racket and serves up a data-driven window into the player’s performance. It logs the speed of your swing, the number of each type of shot, the spin you put on the ball, and where on the strings you’re connecting.

Tennis players will recognize Challenger’s basic form factor as a “dampener,” a device usually made of rubber that cuts down on some of the vibration in the strings. It clips onto the strings near the bottom of the racket head, just above the handle. But unlike its rubbery forebears, Challenger’s embedded sensors record motion, vibration, and other data to keep track of the user’s play.

It’s clear the designers -- who include a certified tennis coach and several players -- have put a lot of thought and effort into the features, design, and durability of the device. Challenger is made of aircraft-grade aluminum to be both light and strong, and features a hinged clasp that can be attached or detached in seconds. The screen is high-contrast to compete with direct sunlight, and is being tested extensively for its ability to take repeated hits without breaking.

Most of the raw data can be accessed directly on the device, but more details are available by syncing it with a mobile app over Bluetooth. The app supports multiple user profiles so it can account for the physical characteristics of each racket and how it’s strung, as well as track each user’s training goals. It can also create graphs and visualizations to help a player learn from the data. There’s even a competition mode that can record data without syncing, to account for tournament rules that prohibit outputting data during a match.

Challenger’s Kickstarter campaign runs through June 26, 2014. Learn more at, or by watching the video below.

Ted Burnham

Professional Combobulator


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