Windsurfing & Kitesurfing is a lot about feeling. The feeling when you get planing, when you sail in waves higher then you, or when you just enjoy a ride during sunset. When you are back on the beach, you have a feeling about your session. Was it good, was it bad, was it fast. But mostly you don't know why something was good or bad.
It's safe to download the app. Matthias Koch is the developer of WindsportTracker that can be found in the Sports category. The tool has been downloaded and set up by over 10K users and the most recent update was released on Oct 10, 2020.