There is a 3rd alternative...
Atolia, the one and only workspace your team needs
Atolia is a power-packed all-in-one digital workplace: Chat, Video calls, Tasks & Projects, Calendars, Documents, Notes...
Accelerate your team's collaboration game.
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Why choose Element or Mattermost?
Both Element and Mattermost offer a free version of their tool, roles management, custom domain name, chat, file sharing, mentions, groups/channels, GIF and emoji, and threads. However, Mattermost stands out with features such as 1-1 and group video calls, screen sharing, audio call, task management, "Do not disturb" mode, unlimited storage, and training resources. Element, on the other hand, offers features such as AI, newsfeed, and notes-taking, which Mattermost does not provide. Both tools offer mobile, web, and desktop apps, integrations & API, on-premise deployment, SAML/SSO authentication, end-to-end encryption, and two-factor authentication.