Mattermost is described as 'Self-hosted platform for chat, workflow automation, voice calls, screen sharing, AI-powered features, third-party integrations, and team messaging' and is a very popular Group Chat app in the social & communications category. There are more than 100 alternatives to Mattermost for a variety of platforms, including Web-based, Android, iPhone, Windows and Mac apps. The best Mattermost alternative is Element. It's not free, so if you're looking for a free alternative, you could try Element or Discord. Other great apps like Mattermost are Slack, Stoat Chat, Zulip and Rocket.Chat.
Provides secure collaboration with end-to-end encryption, supporting chat, voice, and video calls. Available on all major platforms, it enables digital sovereignty with a decentralized design and interoperability through bridges to systems like Slack and Teams. Includes enterprise-grade SaaS.
An integrated platform for text and voice communications. Offers tailored channels for different topics, customizable moderation tools, low latency for fluency, and managed user roles for optimal community facilitation.
Open standard protocol enabling decentralized, encrypted instant messaging, VoIP signaling, IoT device connectivity, and persistent data management across federated servers without central control or single points of failure, bridging communication platforms.
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.
Instant messaging platform supporting text and voice channels, live video calls, secure screen sharing, private group chats, customizable permissions, moderation tools, bot integration, privacy-focused design, open-source development, and cross-platform use.
Threaded group conversations combine live and asynchronous messaging, separating topics for organized collaboration, supporting open-source, cloud, and self-hosted deployments, secure communication with encryption, and multi-platform access for diverse teams.
Open-source chat server supporting real-time group, direct, and private messaging, video calls, file sharing, helpdesk chat, API integrations, desktop notifications, emojis, LDAP authentication, cross-platform apps, and customizable extensions for teams.
It is the brand new, and fastest ever, Matrix client. It is for personal and community use, and will support enterprise functionality later this year.
Utopia P2P Ecosystem. Utopia is a feature-rich platform that is specifically designed to protect privacy of communication, confidentiality, and security of personal data. Utopia is a decentralized network, with no central server involved in data transmission or storage.
Lightweight communication platform with unlimited channels, seamless voice and video, screen sharing, private file sharing, advanced task and calendar tools, robust privacy features, emoji and thread support, and multi-platform efficiency for gaming or team communities.
Offers secure messaging with end-to-end encryption, unlimited free calls, group chats for up to 250 members, rich media sharing, emoji reactions, AR lenses, self-destruct messages, affordable international calls, community channels, and robust privacy across devices.
Peer-to-peer group chatting over Tor and IPFS, with local-first encrypted messaging and no central servers, offers privacy-focused decentralized collaboration for teams, supporting desktop and mobile. FOSS, open to contributors, and avoids surveillance-based tracking.
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Federated, bridged with many IRC networks.