Review on Coollang Koospur Bluetooth Tennis Racket Sensor Tracker: 🎾 Motion Detector Analyzer for Android and iOS Smart Phones (Black) by Carl Morgan

I was about to write a negative review after ten righthands and ten backhands on my Topspin Pro only to find that the sensor registered a total of ten volleys. I tried this in two games and also used my Babolat POP to compare the results. I know from experience that POP returns a fairly accurate count of hits. I was pleasantly surprised to see that this sensor recorded almost the same number of hits as the POP. The speed of the strikes was pretty close too. (I tried Coollang because POP is no longer sold and it looks like Babolat is also ending its support. I want something to replace POP in case it breaks one day.) So I will keep using Coollang. UPDATE: I found a way to attach a sensor that works quite well. I bought a strong clear Velcro like the EZ Pass transponders. Attached one side to the handles of my racquets and the other to the sensor. I also had to glue the connector as the sensor and connector sometimes come loose. The sensor still works and gives similar numbers as Babolat POP. UPDATE #2: My experiment with this sensor is complete. Despite the fact that I used velcro the sensor did not detach from the racquet, in the end the top of the sensor detached exposing the electronic innards. I tried to glue the sensor back but the glue didn't hold. As a result, I stopped using Coollang.