collaboration

Nextcloud

Germany

Open-source, self-hosted content collaboration Hub from Nextcloud GmbH (Germany): Files, Talk, Groupware, Office, local AI Assistant, and Flow—an on-prem alternative to Microsoft 365-style suites.

Nozbe

Poland

Polish task and project management SaaS with task-based communication, multi-workspace separation, offline apps, and vendor-hosted EU primary infrastructure.

Stackfield

Germany

German all-in-one collaboration suite (chat, tasks/projects, video, docs) with optional client-side end-to-end encryption and Germany-hosted cloud or commercial on-premise.

Wire

Switzerland

Swiss open-source secure messenger from Wire Swiss GmbH: always-on E2EE messaging, calls, and files (MLS), cloud or on-premises, for regulated teams and public sector.

mailbox (formerly mailbox.org)

Germany

German paid digital workplace from Heinlein Hosting GmbH: secure email with PGP/S/MIME, Drive, browser Office, Meet, and business Admin on dual Berlin data centres.