Syncios Backup

Has anyone tried Syncios to backup their phone? Thanks

As far as I know third-party backup solutions don't work on GrapheneOS.

The only option is to use Seedvault and do per-app backups for the apps that don't use it (e.g. Signal).

Have a look at this video for how to use Seedvault:
https://youtu.be/eyWmcItzisk