Maximize your messaging experience with efficient communication, speedy delivery, and optional end-to-end encrypted Secret Chats. Engage in unlimited channels and groups up to 200,000 members. Enhance chat management and media sharing with Telegram Premium and its exclusive benefits. All core features remain...

Exchange messages without SMS fees using this app for iPhone, Android and desktop, featuring group chats, multimedia sharing, and video calls. The app requires an internet connection and the latest version for optimal functionality.

Offers unified communication for teams with advanced real-time messaging, contextual features, versatile chat tools, and organized conversations in dedicated channels with integrated file sharing on Mac, Windows, Linux, and mobile platforms for enhanced productivity.

Mattermost is a secure, open source platform for communication, collaboration, and workflow orchestration across tools and teams.

Zulip is the only modern team chat app that is designed for both live and asynchronous conversations. Zulip topics create a separate space for each discussion, so different conversations will never get in each other's way.

Free and secure calls and messages to anyone, anywhere.

Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework.

Provides comprehensive communication features including group video calls, voice calls, fast messaging, photo sharing, and location mapping. Access through mobile and web platforms with real-time notifications, ensuring seamless interactions using multimedia tools.

A comprehensive collaboration platform within Office 365, providing centralized chat, file sharing, and HD video meetings. Accessible on multiple platforms, it offers enterprise-grade security and compliance, customizable notifications, and private to group chat sessions.

An alternative Telegram client based on TDLib, with higher speed, slicker animations and experimental features.

Ripcord is a desktop chat client for group-centric services like Slack and Discord. It provides a traditional compact desktop interface designed for power users. It's not built on top of web browser technology: it responds quickly to input, sips gently from computer...

WeChat is a complete mobile communication and private social networking app. Free, cross-platform, and full-featured, WeChat is the best way to keep in touch with everyone you care about.