Chat & calls

Communications platform that puts data protection first (alternative to Gitter.im and Slack).

Notification infrastructure for developers.

Platform for secure collaboration across the entire software development lifecycle, can be integrated with Gitlab (alternative to Slack).

Customer communication platform (alternative to Intercom and Zendesk).

Push notifications to phone or desktop using HTTP PUT/POST, with Android app, CLI and web app, similar to Pushover and Gotify.

WebRTC application that uses Jitsi Videobridge to provide high quality, scalable video conferences.

Zulip is a powerful, open source group chat application.

The most private and secure chat and applications platform - now with double ratchet E2E encryption.

Apprise allows you to send a notification to almost all of the most popular notification services available to us today such as: Telegram, Discord, Slack, Amazon SNS, Gotify, etc.

Notification server with Android and CLI clients (alternative to PushBullet).

WhatsApp API gateway exposing messaging as REST endpoints, with a web dashboard, multi-account sessions, and webhook events (alternative to WhatsApp Business API providers).

Fully-featured Matrix client for Web, iOS & Android.

Instant messaging platform. Backend in Go. Clients: Swift iOS, Java Android, JS webapp, scriptable command line; chatbots.

Language-agnostic real-time messaging (Websocket or SockJS) server.

Screego is a simple tool to quickly share your screen to one or multiple people via web browser.

Instant messaging and VoIP platform built for friends, groups, and communities (alternative to Discord).

Conversational app builder (alternative to Typeform and Landbot).

Supports real-time sharing of audio, video, slides (with whiteboard controls), chat, and the screen. Instructors can engage remote students with polling, emojis, and breakout rooms.

General-purpose, lightweight, minimalist WebRTC Server.

Low-latency, high quality voice/text chat software.

XMPP instant messaging server.

Self-hosted web IRC client.

Virtual office / virtual conference application presented as a 16-bit RPG video game.

Scalable open source cross-platform telephony platform.

Simple, secure, fast real-time video conferences up to 4k and 60fps, compatible with all browsers and platforms.

Server for Matrix, an open standard for decentralized persistent communication.

Easy to use but advanced IP PBX system, VoIP gateway and conference server.

Fast, light and extensible chat client.

Modern IRCv3 server written in Go, combining the features of an ircd, a services framework, and a bouncer.

XMPP chat client in your browser.

Simple, secure, scalable real-time video conferences up to 4k, compatible with all browsers and platforms.

WebRTC compatible Selective Forwarding Unit (SFU) that allows for multiuser video communication.

Real time collaboration (RTC) server.

Modular SIP server (registrar/proxy/router/etc).

Share sensitive information securely with self-destructing links that are only viewable once.

Distributed, secure messenger with audio and video chat capabilities.

Stoat is a user-first chat platform built with modern web technologies.

Web Whiteboard to collaborate in real-time on schemas, drawings, and notes.

High-performance and feature-rich chat server for Matrix, and the successor to conduwuit (fork of Conduit).

Realtime server for reliable two-way communication over WebSockets, Server-sent events, etc.

Peer-to-peer chat app that is serverless, decentralized, and ephemeral.

Live Support chat for your website.

Advanced IRC bouncer.

Secured and decentralized communication system. Offers decentralized chat, forums, messaging, file transfer.

Troubleshooting and monitoring VoIP calls.

Mobile messaging platform with a focus on performance and scalability.

Lightweight SIP proxy, location server, and registrar for a reliable and scalable SIP infrastructure.

SIP proxy/server for voice, video, IM, presence and any other SIP extensions.

Whistleblowing software enabling anyone to easily set up and maintain a secure reporting platform.

Federated, end-to-end encrypted messaging service for the web, iOS, and Android, supporting text, photos, video, and WebRTC video and audio calls.

Video conferencing server that is easy to deploy and that requires moderate server resources.

Modular IRC server written in C++ for Linux, BSD, Windows, and macOS.

Anonymously share files, browse and publish _freesites_ (web sites accessible only through Hyphanet) and chat on forums.

Web interface for multi-platform voice switch called FreeSWITCH.

Responsive web IRC client with theming support.

A web frontend for WeeChat.

A simple, fast, and reliable chat server powered by Matrix.

Multichannel notification server with support for Email, Mobile Push, Web Push, SMS, messaging and a javascript plugin.

One-Time-Secret sharing platform with a symmetric 256bit AES encryption in the browser.

Distributed IRC client, meaning that one (or multiple) client(s) can attach to and detach from a central core.

Portable and lightweight Internet Relay Chat server for small or private networks.

Scalable and high performance web conferencing system.

Modular, advanced and highly configurable IRC server written in C for Linux, BSD, Windows, and macOS.

Real-time cam-2-cam video calls & screen sharing, end-to-end encrypted, to embed in any website with a simple iframe.

All-in-one Dockerized easy XMPP solution, including web admin and clients.

Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks.

Keep secrets out of emails or chat logs, share them using secure links with passphrase and expiration dates.

Notification server for relaying push notifications via Matrix, similar to PushBullet and Gotify.

XMPP server implementation in Java.

All-in-one customer engagement platform from lead-gen to post-sales, from WhatsApp to your website. With omni-channel live agents and AI-powered chatbots (alternative to Intercom, Zendesk, Tawk.to and Tidio).

IRC without netsplits. Distributed IRC server, based on RobustSession protocol.

Complete, modular and scalable SIP server, includes a push gateway, to deliver SIP incoming calls or text messages on mobile device platforms where push notifications are required to receive information when the app is not active in the foreground.

Next-Gen self-hosted chat server and clients.

Full-featured PABX system, with call queues, built-in web conferencing, live chat and social media messaging all on one system.

Community-driven Matrix homeserver, the continuation of conduwuit focusing on user experience and new features (fork of Conduit).

Web-based open source GUI that controls and manages Asterisk.

Software framework for decentralized, peer-to-peer networking.

Online whiteboard, audio/video conferencing, screen sharing, shared code editing and optional session recording/playback.

Universal communication platform which preserves the user's privacy and freedoms.

Web frontend from Salut à Toi.

Web-based, end-to-end encrypted email platform that uses an independent PKI.

Feature-rich and easy to configure XMPP server.

Multipurpose, multi frontend, libre and decentralized communication tool.

VoIP troubleshooting and monitoring platform.

Platform for your corporate communications, based on the advanced architecture, with support for UltraHD video conferencing, built-in messenger with personal and group chats, and a free version for up to 1,000 users.

Instant messaging and collaboration tool with private and group chat rooms, continuous voice and video meetings, files sharing, issue tracking with integrated task board (alternative to Slack).

Full-featured IPBX solution built atop Asterisk with integrated Web administration interface and REST-ful API.

Transit class4 softswitch(SBC) with integrated billing and routing engine and REST API.