For photo syncing, I use PhotoBackup

Thanks, but I wonder for how long this will continue to work, considering that the latest PhotoBackup build is from November of 2016 and it targets Android 4.1 (newer Android versions will probably require a higher version target). In the long term, I think that migrating to Immich or Ente is the better option. Both have official, well-maintained FOSS apps, that are available on F-Droid, and the backend services can be completely self-hosted.

• Immich
  • App
    • F-Droid: https://f-droid.org/en/packages/app.alextran.immich/
    • GitHub: https://github.com/immich-app/immich
  • Self-hosting: https://immich.app/docs/install/requirements
• Ente
  • App
    • F-Droid: https://f-droid.org/en/packages/io.ente.photos.fdroid
    • GitHub: https://github.com/ente-io/ente
  • Self-hosting: https://help.ente.io/self-hosting/