Konva Fitness is RMRJT Pty Ltd, a small company in Melbourne, Australia. The product was built by a software developer working alongside a personal trainer who was running a real practice at the same time.
The starting point was not a market or a category. It was the trainer's actual week: the programmes written and rewritten for each client, the bookings arranged over text message, the check-ins that lived in a notes app, the chat threads spread across three messaging apps, and the nutrition advice that never quite made it into anything a client could look at later.
Each of those became a part of Konva only once it was needed by someone with real clients, and each one was shaped by watching what happened when it was used. That is slower than shipping a checklist of features. It is also why the things that are in the app work the way a trainer expects them to.
It is still a small team, and the people who answer the support inbox are the people who write the code.