This app was mentioned in 4 comments, with an average of 1.50 upvotes
> I'm starting to think the best way may just be to use nextcloud and sync around text files.
I looked at the the other day, and QOwnNotes seems to be a pretty nice piece of software on desktop. It doesn't have a mobile client, but it stores notes as markdown files, and I've seen people recommend Writeily Pro and setting its root folder to the your notes sync folder. I'm considering giving it a try at some point, since it looks like the best option so far.
On Android, I use Writeily Pro, a beautiful markdown editor (it was just handed off to a new maintainer, so it lost all its reviews on google Play), and sync the notes using Syncthing. On my computer I edit them with gedit.
Admittedly, it could use a little UI work and a better icon, but it's small, works in Markdown, and just uses a directory, any syncing has to be done with other apps handling that directory.