Many of us share the same hobbies and sports such as tennis. Even if we are not professional players we work hard to constantly improve our game. Nowadays, tennis players have a lot of different opportunities to analyze and improve their game. The problem for us was finding the perfect tracking solution that could say: "Hey, nice shot! but keep your arm straight!" or "Good backhand. Try to hit the ball with a full swing, from low to high!".

Some devices and apps are better in providing detailed data and analysis of your performance, while others inform you of simple statistics like how many forehands you did, but none of them tell you what to do to play better.

So, we designed and built an app able for wearables to detect common tennis errors and suggest how to fix them. In details, the app on the smartphone collects motion data from the wearable device. They are sent to the cloud service which, with the appropriate magic, processes the result and sends it back to the app. In this way, the user receives an immediate feedback about the quality of the shot and the app suggests how to correct it in real-time.

In short, we have built our personal tennis coach... and it stays on our wrist!