the tennis mobile app of the future


TennisTension Ltd. released the first mobile app which measures consistently and with extreme accuracy the racquet's string tension just in few seconds - the error of the measurements is less than 0.2 kg.

Tested, approved and used for months on the Tennis Atp tour by several Bulgarian ATP professional players and national single and doubles multiple champions.

At  ATP Sofia 2019 in January, 3 of the seeded players tested, approved and decided to use TennisTension as an instrument to check the momentous tension of their racquets. They gave us valuable recommendations to include the string pattern, hybrid stringing and the string opening size influence. We managed to fulfil all their demands and to upgrade our product to the highest possible level.



• The user has to learn how to produce the proper ringing sound close (2 to 10 cm) and in front of the phone microphone. Find the microphone which uses single, very small hole either at the top or at the bottom of the phone.

• Remove the dampener - if you have. 
• Tap the racquet string very gently several times every 1 or 2 sec. with a stiff object. The best way is with pen or pencil, or use another racquet, fingernails, etc.
• While ringing, the resonating racquet string must stay 2 to 10 cm from the microphone, in front of it, especially in a noisier environment. It is shown well in the YouTube video provided for TennisTension mobile app for Google play and App store.
• To receive the exact momentous string tension, define all the necessary racquet and string parameters. If you don't know some of them, default average values are taken for the calculations or the last values that the user put it in. Consider the tension loss.
• TennisTension measures the average tension between main and cross strings of the racquet (for example, if a racquet is strung 25/24 kg, the measurement result will be 24.5 kg).
• String tensions of hybrid strings could be measured as well.
• The error of the measurement result is less than 0.2 kg.
• Calibration is provided, though it is not necessary to use it.

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©2019 by TennisTension Ltd.