http://qgu356nwwy7dweo276qk6rkts4pgpgm3vjjmedsifunu5yope52vdbid.onion/index.php/Tox
Specifically, Tox employs Curve25519 for its key exchanges, xsalsa20 for symmetric encryption, and Poly1305 for MACs. [9] Because the tox protocol can be used by many different applications, and because the tox network broadcasts the used client, it is also possible for clients to use additional encryption when sending to clients which support the same features.