Syncthing is free, open source software that can be used to easily synchronize an Obsidian vault between your computer and phone/tablet. Not only free, but completely secure, private, and blazing fast. Here are links to an article I wrote explaining how to use it.
- Biscotty’s Workshop not mobile friendly :-(
- Substack
- Medium.com
SyncTrayzor is a nice GUI package & tray icon for SyncThing. I’ve been using it for years.
I haven’t used that one. There’s a gtk gui on flathub, too. I just used the browser interface here because it’s universally available (tmk).