Comment by silvanocerza

You can use iCloud but it's quite slow.

There are different solutions really, some people use Git and treat the whole vault as a repo. Though I find it quite annoying to manage, also cause not every platform supports git.

That's also why I started writing a plugin to sync with any GitHub repo, it uses the GH REST APIs so it can be used on any platform. https://github.com/silvanocerza/obsidian-github-sync

I'm still actively developing it but the core features work nicely.