messaging

A cloud-based mobile and desktop messaging app with a focus on security and speed.

Signal is an encrypted communications application.

A feature-rich desktop native client developed for Windows, MacOS, and Linux platforms, allowing you to enjoy the instant messaging service on your PC.

SimpleX - the first messaging network operating without user identifiers of any kind - 100% private by design! iOS, Android and desktop apps 📱!

An open source SIP phone for voice/video calls, instant messaging and conference calling.

Peer-to-peer chat application with end-to-end encryption for private messaging, calls, and file sharing.

Graphical client for the Soulseek peer-to-peer network

End-to-end encryption for things that matter. Keybase is secure messaging and file-sharing.

A decentralized and secure messenger app

High-Performance server for NATS.io, the cloud and edge native messaging system.

Command-line interface for Slack Web API

Command-line interface for Slack Web API

Self hosted local network messaging system

Unofficial UWP Instagram Direct Message client for Windows

FOSS messaging and emailing app that combines common web applications into one

ttth (talk to the hand) is an electron based desktop app for online services like WhatsApp, Threema, Telegram, Twitter, Google and several others.

A privacy-first WhatsApp Web desktop client

Secure Exchanges OASF client for Windows.

A lightweight, distraction-free desktop wrapper for Facebook Messenger.

The frontline communications and employee engagement app that connects every employee with the modern workplace.

A chat app that puts you first.

Self-hosted, federated chat platform with voice, video, threads, and scheduled events.

WhatsApp automation and broadcast platform

Kahla is a cross-platform business messaging app.

Brosix is an Instant Messaging Software for Businesses, providing encrypted, real-time communications, across multiple applications, to streamline how day-to-day business gets done.

Send instant messages to computers on your LAN - a net send and msg.exe alternative that needs no server.

Kotatogram Desktop, being based on Telegram Desktop, has all its features, but it also has some more useful and cosmetic features.

Cross-platform desktop client for Facebook Messenger

Secure two-way communication between clinicians and patients, integrated with EMIS Web and SystmOne clinical systems.