Marcus Fehn, writing on Ulysses’ weblog:
We have always tried to be backwards compatible as best we could. Sometimes, this meant supporting four years worth of old systems, for the very small number of users still on one of these systems. While it didn‘t hurt much, it still hurt, because with every new device, every branch of every OS, we had to come up with (and maintain) explicit solutions for the old systems. At present, Ulysses runs on iOS 10 or later, as well as OS X 10.11 El Capitan or later. Some stuff was tricky.
Going forward, we will switch our policy to a simple rule of thumb: Support the current system, as well as the one that shipped before. It’s much more efficient, and it helps us move a bit faster. So once the new systems are live this fall, any new version of Ulysses will require either iOS 12 or macOS 10.13 High Sierra.
Marcus goes on to explain a bit more about why they’ll be supporting High Sierra after Catalina releases this fall — mostly because some of their users still use 32-bit apps. But I absolutely love how open and honest the folks behind Ulysses are about this. As we move further into an era where subscription-based apps are the norm, more developers should be making these sorts of policies public.