Slack Alternatives

Microsoft Teams is your hub for teamwork, it brings together everything a team needs from chat and threaded conversations, meetings & video conferencing, calling, and content collaboration. With you can instantly go from group chat to video call with the touch of a button. Securely connect, access, share, and coauthor files in real time. While staying organized by keeping notes, documents, and your calendar together.

A VoIP application and platform designed for creating communities and connecting gamers, and people rallying around specific causes. The Discord client is a free to use and can handle text, image, video and audio communication between users in a chat channel. Currently over 250 million users use the software to connect with others across the globe.

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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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.

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.

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.

Jitsi is an open-source project and software toolset that allows you to easily build and deploy secure video conferencing solutions. At the heart of Jitsi are Jitsi Videobridge and Jitsi Meet, which let you have conferences on the internet, while other projects in the community enable other features such as audio, dial-in, recording, and simulcasting.  Jitsi supports popular protocols such as SIP, XMPP/Jabber, ICQ/AIM, Windows Live, Yahoo!, Google Hangouts, OTR, ZRTP and more.

Basecamp is a project management and collaboration tool that allows groups of people to share files, meet deadlines, assign tasks, and give feedback. The software is web-based an can be accessed from any device and anywhere as long as device has a web browser.

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.

Threema is a messenger application that puts security and privacy first. The application is designed to generate as little user data as possible. The service is fully GDPR-compliant and the company has its own servers hosted in Switzerland. With Threema you can keep in touch with friends, family and co-workers while enjoying privacy and rest assured that you personal data is not commoditized.

AirSend brings everything you need to get work done into a single, elegant workspace. It's a communication and collaboration tool that brings chat, voice and video calling, file sharing, task management, and more into one workspace so you can easily collaborate with team members and clients. With Airsend you can post messages, have voice/video calls, share and organize files, and complete projects together with your team. The free teir of AirSend workspace comes with 100 GB free storage.