Syncthing works over mobile data as well. You need to enable the option to Run on mobile data in settings. In addition you will need to Enable Relaying and Global discovery on both ends (phone and server)
I have been using it to sync photos and other data from Phone -> Desktop for a few years now and it works fantastically.
I have been using it to sync photos and other data from Phone -> Desktop for a few years now and it works fantastically.