Key Features

Drop-in Microsoft Exchange replacement with full MAPI, EWS, EAS, CalDAV, CardDAV, IMAP, POP3, and SMTP protocol support
Native compatibility with Microsoft Outlook without requiring client-side MAPI extensions
Integrated suite covering email, calendar, contacts, tasks, notes, chat, video conferencing, and file storage
Built-in mobile device management (MDM) for enterprise fleet administration

Replaces

Microsoft ExchangeMicrosoft 365

Headquarters🇦🇹 Vienna, Austria

Founded2019

Open SourceYes

Free TierYes

GDPR CompliantYes

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