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
Tox is a decentralized communication platform focused on providing secure voice and video calls alongside text messaging, while ChatSecure emphasizes privacy with OTR messaging and integration with Tor. Both are open-source, but Tox offers broader communication features, whereas ChatSecure is more privacy-centric.