Keybase Go library, client, service, OS X, iOS, Android, Electron
Open Source Email App for iOS
Open source email service with a strong focus on security and privacy
LXMF client for Android, Linux and macOS to communicate with people
A glossy Matrix collaboration client for iOS
A Decentralized, Onion Routed, Private Messenger
Instant messaging platform
Wire for iOS (iPhone and iPad)
Home to the Signal Protocol and other cryptographic primitives
Secure email that protects your privacy
The original full-platform IM communication layer framework
Video conferencing and collaboration platform
An iOS client library for integrating multi-party communications
A free (libre) open source, mobile OS for Ethereum
Development toolkit for Web Services and XML data bindings for C & C++
Remote control. Support VNC, RDP, Terminal, SSH, TELNET etc
The Free & Popular FLARUM Web Software in a Complete Virtual Machine
ChatSecure is a free and open source encrypted chat client for iOS
Infrastructure for building composable apps and services on the IPFS
Legacy mobile Rocket.Chat client in Swift for iOS
A super easy WiFi hotspot user management utility for Mikrotik router
Simple and lightweight IM client
C# Framework for WinCC OA Open Architecture connectivity (XMLRPC)