CC Cloud currently supports:
- Dropbox [Android, iOS]
- Microsoft OneDrive [Android, iOS]
- Box [Android]
- Amazon Cloud Drive (as of CC V4.2.2) [Android]
- A calibre library stored on the device, either in main memory or on an SD Card [Android]
More providers may be added over time.
Note: CC Android no longer supports Google Drive. That support ended when Google stopped supporting the feature that CC uses to login to a cloud provider.