Not had too much time to try it so far, but UBPorts is pretty nice. The UI and the web browser are impressive. It's a bit locked down out of the box though, I'd like to be able to install normal packages without jumping through hoops.
#Mobian is closer to what I want from "Linux on mobile". The UI is a bit choppy compared to Ubuntu Touch, but having full access to ARM Debian packages is great
PinePhone stuff
For example, it was as easy as on desktop to add the Syncthing repository and get my files syncing across