Category
Files & cloud
3 groups, 11 open-source listings. Each group is one job; pick the one you need.
Groups3
What each one replaces, and how many open alternatives it has
Cloud storage & sync
6open alternatives3do the whole job
Keeping files in sync across devices.
Replaces Dropbox, Google Drive, Microsoft OneDrive, iCloud Drive
Sending big files
2open alternatives1does the whole job
Sending a file too big for email.
Replaces WeTransfer
Backup
3open alternatives3do the whole job
Backing up a computer.
Replaces Backblaze, Time Machine