docs/wiki/2.08-Choose-Sync-Backend.md
Sync backs up and synchronizes your full Super Productivity data (tasks, projects, time tracking, settings, archives, and so on) between this app and a remote location or another device. You configure one sync provider per device; each device can use a different provider (the Sync provider setting is not synced between devices). For a detailed comparison of providers, see [[3.08-Sync-Integration-Comparison]]. For how to configure the one you choose, see [[2.09-Configure-Sync-Backend]].
It is not a requirement to use any sync backend if you only use Super Productivity on a single device. Ensure that you have backups configured and that you know how to [[2.02-Restore-Data-From-Backup]] in case of data corruption from other errors.
The app is moving to a new operation-based sync model (changes are sent as operations instead of full data blobs). SuperSync is the backend built for this model and is where new development is focused. The other providers (Dropbox, WebDAV, Local file) use the current file-based sync and remain supported. The word “legacy” in the code refers to the older technical implementation, not to deprecation or removal—the developer has stated that WebDAV and Local file are very likely to remain available for the foreseeable future. Choose the option that fits your setup and risk tolerance.
In the Sync provider dropdown you will see:
Local file sync stores data in one folder on your device. The app warns: do not use file-syncing tools (e.g. Syncthing, Resilio) to sync that folder between devices—they can cause conflicts. For syncing between multiple devices, use WebDAV, Dropbox, or SuperSync.