It works great on android. I have a laptop, my phone, and a NAS all syncing. The NAS does most of the heavy lifting. Its a little P2P data ship-of-Theseus as I replace machines over time. As long as I don't throw my laptop, phone, and NAS all in the river at once, my data is safe. The encrypted sync feature of sync-thing lets me and my so-inclined friends use each other as offsite backups. Its honestly the best open source software other than GNU apps or Linux I have ever used.
Make sure you setup basic version control in syncthing, I had some issues with my daily notes getting clobbered because they were autogenerated by multiple obsidian instances.
I saw that the OP already replied, but wanted to share how I approach this myself. I have a desktop, laptop, and phone that I wanted to keep synced up, so I actually used it as an excuse to setup my own git repo on my NAS (which I wanted to do anyway).
The only tricky part has been dealing with git on iOS. I have to use a particular app (Working Copy) and some shortcuts to get the syncing behavior consistent. But it is doable!