Slack Alternatives for Android

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.

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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.

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.

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.

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.

Flock is ateam communication app and online collaboration platform that comes with team messaging, project management and other great features that improve productivity and boost speed of execution. With Flock, you and your team can connect better and reach the goal of your organization faster.

WhatsApp is free messenger app for chat and voice over IP, owned and managed by Facebook. The application allow users to send text and voice messages, make voice and video calls and share images, media files and user locations with friends and family.