Fairphone 4. Ubuntu Touch is supported at a manufacturer level, it supports Postmarket OS, easy user serviceable, SD card slot (which apparently is rare now). No headphone jack but that’s about the only downside. I’m running one with Calyx and while it is a little older of a phone - it’s perfectly fine.

Hopefully this leads to a lot more development of and for Ubuntu Touch. Biggest issues it faces are lack of compatibility and lack of apps. I think the core is solid though. I used it for a week when switching from iOS (so no Android background) and enjoyed it, but a few too many minor issues built up and I ended up going to Calyx.