End-To-End is a crypto library to encrypt, decrypt, digital sign, and verify signed messages (implementing OpenPGP)

ChatSecure is a free and open source encrypted chat client for iOS that supports OTR and OMEMO encryption over XMPP.

Open-source XMPP client for Android

Session Desktop - Onion routing based messenger [DEPRECATED SEE README]

💬 Real-time xmpp chat application with video calls, file transfer and encrypted communication.

coyim - a safe and secure chat client

minimalistic secure XMPP client in OCaml

A place for useful crypto-related resources plus some of my fav stuff

Off-the-Record Messaging Protocol version 4. -This is a draft- This repository is a mirror of http://bugs.otr.im/otrv4/otrv4

📱 Wire for iOS (iPhone and iPad)

A Go implementation of the OTR 3 protocol, with libotr 4.1.0 feature parity

Officially supported Psi plugins

A new implementation of OTR with support for version 4. This is a mirror of https://bugs.otr.im/otrv4/libotr-ng

Off-the-record (OTR) messaging protocol, purely in OCaml

OTR4J: Off-The-Record messaging encryption written in pure Java

Off the record plugin for HexChat

Off-The-Record messaging encryption written in pure Java

😈 An end-to-end encrypted chat system based on the OTR protocol

OnionComms is a repository of script to run an onion server and guides to configure client side applications to connect to any onion service that uses the same protocol, therefore, onion communications.

Termux IRC client with post-quantum OTRv4 NIST Level 5 throughout. Rust core: ML-KEM-1024 brace key rotation, ML-DSA-87 hybrid auth, Ed448 ring signatures, double ratchet, hybrid PQC SMP (ML-KEM-1024 + ML-DSA-87 per-step signatures + ZKP). ZeroizeOnDrop on all secrets. I2P SAM / Tor / TLS 1.3. Zero traces on exit.