Microsoft Teams.

Team collaboration and video conferencing platform

Facts

Jitsi
Open-source video conferencing platform, self-hostable
US · open-source
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OpenTalk
German open-source video conferencing platform with focus on privacy and GDPR
DE · open-source
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Teamwire
German enterprise messaging with GDPR compliance and MDM
DE · commercial
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Stackfield
German project management and team communication with encryption
DE · commercial
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Wire
End-to-end encrypted collaboration platform by Wire Swiss GmbH (Zug, Switzerland)
CH · open-source
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Element (Matrix)
Decentralised messaging based on the open Matrix protocol
GB · open-source
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Nextcloud Talk
Video/voice within Nextcloud; self-host.
DE · open-source
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Matrix / Synapse
Matrix homeserver; self-hostable.
GB · open-source
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