Tennis Meets Technology: Zepp Tennis Sensor

By Matt Locke

Following the trend in fitness trackers, the market for “connected” tennis devices seems to be poised for continued expansion with the introduction of a few new devices. First came Babolat’s Pure Drive Play, the world’s first connected tennis racquet. Now, we’ve been introduced to the Zepp Tennis Sensor, a competitor that is newer to the market in recent months. Also coming soon is the Shot Stats Challenger, a dampener style device that attaches to any racquet, providing instantly viewable data on swing speed, impact location, spin level, shot quantity and more. After testing the Zepp Tennis Sensor, I came away feeling that it does fill a slightly different slice of the market compared to the Babolat frame. Let’s take a closer look.

Connectivity & Usability

The Zepp device is incredibly easy to connect to your smartphone or tablet via Bluetooth after you set up your profile. Whereas I often had difficulty connecting my Pure Drive Play to my phone, the Zepp paired up instantly every time. I also enjoyed the fact that there was an audio cue announcing when it was connected or disconnected (this feature can be turned off). If your phone is connected during play, your data gets uploaded automatically or the device can store up to 200,000 swings offline until the next time you sync it.

The Zepp also comes with a charging cradle that connects to a computer via USB, but the actual data review is all app based (the Babolat has a computer based interface in addition to the app). Powering on and off is easy and it provides a flashing indicator when the battery gets low. Attaching the sensor to the handle of the racquet is easy, as the silicone mount slips on quickly provided you properly line up the sensor inside the mount. Initially, I was a bit concerned about how its placement on top of my overgrip could create obstruction, but I was pleasantly surprised at how little I noticed the mount on my handle during play.

The primary sticking point for players will be the fact that Zepp lists the sensor and mount at a combined weight of 18 grams. That is a significant amount of weight to be adding to the handle of any racquet, impacting the static weight and the balance of your frame. Players who typically use lighter, head heavy frames would probably have a more noticeable adjustment with the Zepp sensor attached. While the connectivity features may not be as rich as the Babolat Play (currently there is no computer based option or social network features), the Zepp does provide a very user friendly setup while also allowing you to play with your racquet of your choice.

Data Collection and Review

The Zepp Tennis Sensor utilizes dual accelerometers and a 3-axis gyroscope to analyze your swing path and racquet speed. This gives it the ability to provide data on what stroke is hit, the sub type of each stroke (flat, slice, topspin) and the power level of each shot. There were some noticeable accuracy issues with the sensor determining what kind of stroke I was hitting. I had several sessions where I did not do any serving yet it gave me a reading that included a significant level of serves and smashes. The sensor appeared to have trouble recognizing that high forehands were not serves or smashes.

It was more accurate with the sub types of each stroke as the breakdown of flat, topspin and slice shots was right where I expected it to be. When looking at topspin, the Zepp does have a more limited view than a product like the Pure Drive Play, as it does not (currently) give you a measure of how much spin is present. It simply presents a surface view of your overall shot selection. This feature would provide a good baseline for what shots a player is favoring and could provide a way to focus training sessions on developing shots in which they feel less confident.

The power level is graphed out either as a combined visual of all stroke types or individual shot type. The chart also shows your maximum power level for each stroke as well as your average. This offers solid potential to track your match fitness and how your power level fluctuates over the course of longer periods of play.

Another important feature that was just recently added is the impact locator. This tool allows you to breakdown each stroke type and see where on the string bed you are making contact. Much like its competitors, the Zepp appears to estimate the location by detecting the frequencies given off by the string bed on contact and applying an algorithm. I found it to be pretty accurate based on what I know about my typical contact point. The impact locator is a great way to identify footwork, spacing and timing issues with your strokes, and its recent inclusion in the app increases the overall functionality of the Zepp.

Perhaps the biggest addition to the Zepp is the new 3D Serve Analysis tool. This feature logs each serve you hit as a three dimensional model. You can then view a video playback of any serve you hit and see the full swing from take back to follow through. Within the app, you can view each serve’s racket speed, estimated ball speed, spin level, backswing and impact time. The feature also allows you to compare any two serves as well as overlay a pro’s serve with yours for comparison. The Zepp is the first device on the market to provide a complete model of a swing, making the Serve Analysis tool the most valuable aspect of the Zepp. While it shouldn’t be viewed as a way to learn or fix the serve without proper coaching, it could be a tremendous asset to a player trying to identify areas for improvement.

Final Verdict

The Zepp Tennis Sensor provides a major challenge to its current and potential competition in cost vs. benefit terms. Is it capable of the in-depth detail and evolutionary comparison tools that its competitors have? Not currently. However, it does offer a great overview of a player’s game and can easily be used to chart the development of certain strokes as well as be an effective tool for measuring a player’s match fitness via the power level graphs. Easy to use capability, a significantly lower cost of entry than the Pure Drive Play and the fact that it is compatible with any racquet you choose make it well worth consideration by someone in the market for a connected device to analyze their game.

Zepp will continue to refine the way the system records data as well as add new features and capabilities. The recent inclusion of the Impact Locator and 3D Serve Analysis tools are an indicator of Zepp’s commitment to refining the product. If the thought of having to completely switch racquets and wade into a mountain of data just to analyze your game doesn’t appeal to you, then the Zepp is a worthy candidate. It offers a strong balance of user friendly, simple tools at an affordable price. Join the tennis tech revolution and grab your Zepp Tennis Sensor today!