[yoz-y]

I wanted to jump on the obsidian train but from what I understand I’d need to pay for their sync service to be able to use iOS and headless Linux right?

All other sync methods seem to come with caveats. I’d use iCloud Drive but I was not able to mount it with rclone.

[kepano]

Not necessarily. There are dozens of syncing methods aside from Obsidian Sync (Git, SyncThing, etc) and you can create your own plugin to sync.