Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption. Developed by Project Tox
License: Open Source
Off-the-Record Messaging is primarily focused on providing secure text-based communication with strong anonymity, while Tox offers a wider range of features including voice and video calls in a decentralized environment. Both prioritize privacy, but Tox is more versatile in terms of communication options.