Flock Alternatives

ICQ is the oldest cross-platform messenger and VoIP client. It was originally developed by the Israeli company Mirabilis in 1996, later sold to AOL in 1998. With ICQ you can stay connected with friends, family and co-workers. ICQ provides instant messaging andcan conver audio messages to text.

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.

Imo is a free communication platform used by over 200 million people across the globe. Imo has clients for both desktop and mobile devices and lets you video chat with family and friends and meet new friends and share stories on the ImoZone. Imo can handle audio and video calls no matter if they are abroad or not.

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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.

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.

A web-based service for internal instant messaging and private chat for organizations. HipChat provides one-on-one and group and topic-based chat, as well as cloud-based file storage, video calling, searchable message-history and inline-image viewing. You can use HipChat natively on your desktop or mobile phone, or web browser. HipChat is available for Android, iOS, macOS, Linux, Windows and the Web.

With Wickr you can control and protect your most critical communications. Unlike other video conferencing and collaboration platforms, Wickr Pro is end-to-end encrypted and built to scale for any Enterprise. Featuring unmatched security, total compliance, secure file transfer, SSO and MDM integration, Bots, full administrative controls and a whole lot more.

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.

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.

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.

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.