I know it's probably no help on iOS, but for people on android or no mobile requirement, just push and pull to a git repo. You can probably even set up a cron or something to sync regularly.
GitSync works for me both on Android and iOS. I'm not using it that frequently tho, and you have make it a habit to open GitSync first, sync the changes (pull) and then open Obsidian. Also, after changing the notes you should again open GitSync and do a sync (commit + push).