Overall, this product is wonderful in theory: It allows me to pick gyms anywhere in Germany, without having to join any specific gym.
The iOS app that I used, however, makes it shockingly hard to actually find the things I want to do. In practice, I've given up: I simply go to the same gym consistently, because, with this app, it's painful to try to find new activities: There's too many irrelevant options, and the options that look interesting are often not available or even fully closed!
I want to find activities near me, so I use the map. This is how the map greets me. This display is not helpful. It's not important to me that there are many potential things I could do, because most of them won't be interesting for me.
Given that there are many options, and there's no recommended options, it's very important that filtering is straightforward.
This filter does not work the way I expect. In the context of working out, I usually think of an activity like Yoga, and then want to find all options. But this filter is a multi-select! So if I pick yoga, and then search for massages later, I'd be picking (Yoga + Massages), and the map does not allow me to distinguish between the results.