Telegram Desktop

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

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Signal

Signal is an encrypted communications application.

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Synology Chat

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

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Nicotine+

Graphical client for the Soulseek peer-to-peer network

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SimpleX Chat

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

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Keybase

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

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DeltaChat

A decentralized and secure messenger app

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Slack Chat API CLI

Command-line interface for Slack Web API

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Slack Chat API CLI

Command-line interface for Slack Web API

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Indirect

Unofficial UWP Instagram Direct Message client for Windows

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Hamsket

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

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HostTalk

Self hosted local network messaging system

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ttth

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

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Secure Exchanges Outlook Area Sign Form

Secure Exchanges OASF client for Windows.

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Kahla

Kahla is a cross-platform business messaging app.

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Brosix

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.

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Kotatogram Desktop

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

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NATS Server

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

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