Just use GNU/Linux (on mobile, too!).
Source: I own a Pinephone and has tried both Phosh-based and KDE-based offerings, there is also Sailfish though. Out of these Sailfish is the only one close to usable as of now.
Ignoring this advice might lead to application termination.
Note I'm not saying it's good, but good enough for me. I've been using Arch, as I find the rate of improvement shows in a rolling release distro, and in my experience, Mobian is no more stable.