Dialog Messenger Alternatives

Gitter is an open-source instant messaging and chat room system for developers designed to make community messaging, collaboration and discovery as smooth and simple as possible. Gitter is provided as software-as-a-service and integrates with GitLab and GitHub repositories to make discussion around code even easier. With Gitter, you can can easily create, organise and grow your communities, inviting others to join just in one click. Over 1.5M users across 100K communities use Gitter to discuss code and development progress.

Viber is a cross-platform voice over IP application that allow people to make free and secure calls and messages to anyone, anywhere. With Viber, you can create group chats and make group calls, send stickers and emojis over chats that are 100% synced between devices, including 1-tap transfer of calls. Viber is available for free on Android, iOS, macOS, Linux and Windows.

Zulip is an open-source real-time chat with an email threading model. With Zulip, you can catch up on important conversations while ignoring irrelevant ones. Zulip provides modern apps for every major platform, powered by Electron and React Native. The software is 100% open source software, built by a vibrant community of hundreds of developers from all around the world.

Work anytime, anywhere with Asana. Keep remote and distributed teams, and your entire organization, focused on their goals, projects, and tasks. From the small stuff to the big picture, Asana organizes work so teams are clear what to do, why it matters, and how to get it done.

A free, unlimited and open-source chat software. Rocket.Chat have set out to be a replacement for email, HipChat & Slack and is provided as Software-as-a-Service (SaaS) or a self-hosted community edition. Rocket.Chat is feature packed and can be used for video conferencing, file sharing, voice messages and more. The software integrates with third-party services like GitHub, GitLab, JIRA, and Confluence and provides an API that can be used for authentication and integration across these services.

Mattermost is an open-source, self-hostable enterprise team collaboration and messaging application. The software can be deployed to on-premis or to cloud instances. Mattermost is designed for internal use within organizations and businesses in financial services, government, healthcare, remote work, and enterprise DevOps, where teams use Mattermost to power collaboration at every stage of the DevOps lifecycle.

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TeamSpeak is a VOIP application that provides military-grade encryption making it ideal choice for your company's, teams and gamers internal, closed-loop communications systems. TeamSpeak is known for its lag-free performance & unparalleled reliability and uptime.

Mumble is a free and open-source voice over IP application primarily designed for gamers. The application features a customizable in game overlay, application skins, conversation recording, and advanced voice activity detection. Anyone can download and use Mumble for free, but if you want your own server, you can rent a managed solution from the company behind Mumble, or host your own.

Matrix.org is an open network for secure, decentralized communication. It gives you a simple HTTP APIs and SDKs (iOS, Android, Web) to create chatrooms, direct chats and chat bots, complete with end-to-end encryption, file transfer, synchronised conversation history, formatted messages, read receipts and more. All conversations on Matrix are replicated over all the servers participating in them, meaning there are no single point of control or failure.

With Google Hangouts, you can keep in touch with through chat, video or voice calls in person or as a group. Google Hangouts is a cross-platform messaging app developed by Google that is available for Android, Chrome OS, iOS, Google Chrome or any browser that is compatible with Google Chrome Extensions.

Pidgin is a chat application which lets you log into accounts on multiple chat networks simultaneously. Pidgin is developed and released fully free and open-source and provides a plugin architecture that allow anyone to build extensions and connections to new networks and third-party services.