BADLAB MAGAZINE: Let's get straight to the point! You will soon withdraw the string tension measuring app "stringster for badminton" from the Google PlayStore and the Apple AppStore. Why? Has the badminton community not embraced the app?

ELMAR SPERLING: In fact, it was with a heavy heart that we decided to take "stringster for badminton" out of the stores for the time being. However, the reason was not that there was a lack of users. Just a few months after the launch, over 250,000 badminton players and stringers worldwide had downloaded the app onto their smartphones for free. But the truth is that after 5 years, urgent technical and content updates have become necessary, at a high cost.

BADLAB MAGAZINE: And you don't want to invest them anymore?

ELMAR SPERLING: Everyone who makes an investment naturally expects a return on this investment at some point. Otherwise it would be a hobby and not an investment. In the tennis sector, we are already one step further: "stringster for tennis" is currently being expanded to include a customer management function for stringers and pro stores - and will thus become a serious business tool that will in future provide stringers and pro stores with ever better support in offering their customers the best possible service for their rackets.

BADLAB MAGAZINE: That sounds exciting. But why don't you do that with the badminton app as well?

ELMAR SPERLING: We have been in talks about this for some time with our badminton cooperation partner YONEX, who provided us with intensive advice and support right at the start of the stringster development. It was only through the cooperation with the YONEX STRINGING TEAM, which strings the rackets of the professionals at the international tournaments, that it became possible to develop a measuring algorithm that measures accurately down to 100g. However, badminton players are less aware of the influence of stringing on the performance of their racket than tennis players.

BADLAB MAGAZINE: What do you think is the reason for this? In both sports, the strings are the interface between the racket and the ball - with a decisive influence on your feel for the ball, the control and the power transmission.

ELMAR SPERLING: That is correct, and the BADLAB string tests also show how different the playing characteristics of strings can be. But in tennis, there is an additional essential factor: spin. While in badminton it is important to hit the ball cleanly and straight in most stroke variations, there is almost no stroke in tennis where you don't need a certain amount of topspin or slice to control the ball optimally. Therefore, an additional string category has emerged in tennis: the monofilament string.

BADLAB MAGAZINE: Interesting, but what does that have to do with the stringster app?

ELMAR SPERLING: The difference lies in the speed of elasticity decrease of the monofilament strings, which dominate among athletic tennis players, compared to the multifilament strings used in badminton. The monofilament strings have largely lost their already lower elasticity after 6-8 hours of intensive hitting - with negative consequences for stroke control and the risk of tennis elbow. Visually, however, this is not noticeable to the player. A monofilament string usually looks good and smooth for a very long time. So to recognize the right time for restringing, you really need a measuring tool here.

BADLAB MAGAZINE: How many different string models, diameters and colors have you actually analyzed for "stringster for tennis" in order to be able to interpret their sound frequency?

ELMAR SPERLING: Due to the great variety of string types/technologies and materials, we are already at over 600 different tennis strings - even though we are still missing some major Asian string brands, for example. We hope to get string samples for analysis here quickly, because we want stringster to be open to all players, regardless of which racket or string brand they prefer.

BADLAB MAGAZINE: Interesting, the focus of "stringster for tennis" is not on Wilson and Luxilon?

ELMAR SPERLING: As the market leader in tennis racquets, Wilson noticed and supported "stringster for tennis" very early on. But just like our cooperation with the badminton market leader YONEX, the goal was never exclusivity. A forward-thinking market leader is always aware that it has a special responsibility for the further development of its sport as a whole - and when the market leader takes this on board, all market participants usually benefit in the end.

BADLAB MAGAZINE: Finally, the most important question: When will we see "stringster 2.0 for badminton"?

ELMAR SPERLING: I can't say exactly today, but I am optimistic that it will be ready in the course of 2024. And then the range of functions will be significantly greater than that of a simple measurement app. "stringster 2.0" will bring players and stringers much closer together.