0up is described as 'Zero-knowledge, open-source, encrypted file sharing service. Files are encrypted browser-side before being uploaded. A shareable link contains the decryption key and is never sent to the server - keeping shared files secure' and is a large file transfer service in the file sharing category. There are more than 50 alternatives to 0up for a variety of platforms, including Web-based, Windows, Android, Mac and iPhone apps. The best 0up alternative is OnionShare, which is both free and Open Source. Other great apps like 0up are Send, pCloud, WeTransfer and Wormhole.