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Self-Hosted Collaboration Calendar Groupware Webmail Contacts CalDAV ActiveSync

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317

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Last Updated: 08-22-2026 02:56 PM (UTC)

SOGo

SOGo adds shared calendars, address books, and a modern webmail interface to your existing Dovecot, Postfix, or Cyrus mail setup, turning familiar infrastructure into a full Exchange competitor. Rather than replacing your IMAP and SMTP servers, SOGo layers collaboration on top of them, becoming the missing link between raw mail delivery and what users actually expect from a workplace communication platform. The ActiveSync implementation synchronizes email, contacts, calendars, and tasks natively with iPhones, Android devices, and Windows without requiring users to manually configure CalDAV endpoints. CalDAV and CardDAV compliance ensures Apple Calendar, Thunderbird (via the official SOGo Connector extension), GNOME Evolution, and Android via DAVx5 all connect without plugins or workarounds. The web interface uses AngularJS Material design with responsive layouts, offering folder management, drag-and-drop calendar scheduling, contact groups, resource booking, and delegation. Shared calendars support free-busy lookups, iMIP event invitations, and per-user ACL permissions for fine-grained access across organizational units. Built on Objective-C with the GNUstep foundation, SOGo delivers exceptional performance: hundreds of concurrent ActiveSync connections from mobile devices alongside webmail and calendar traffic with sub-second response times. With 2,095+ stars and 116 releases, the project has proven its stability in production environments supporting thousands of users. The Docker deployment runs alongside PostgreSQL and memcached.

SOGo
SOGo
SOGo
SOGo
SOGo

Benefits

  • Native ActiveSync Support
  • Two-way synchronization of email, contacts, calendars, and tasks with iPhones, Android devices, and Windows phones. No third-party apps or CalDAV configuration required for mobile users.
  • Existing Infrastructure Reuse
  • Connects to your current IMAP and SMTP servers rather than replacing them, preserving existing mail delivery, storage, and filtering configurations while adding collaboration features on top.
  • Standard Protocol Compliance
  • CalDAV, CardDAV, and GroupDAV endpoints work natively with Apple Calendar, Thunderbird, GNOME Evolution, and DAVx5 without plugins, ensuring broad client compatibility across all platforms.
  • Proven Enterprise Scale
  • Objective-C foundation with GNUstep delivers sub-second response times under thousands of concurrent users, handling ActiveSync device synchronization alongside webmail and calendar access.

Features

  • AJAX Webmail Client
  • Full-featured email interface with folder management, drag-and-drop, message flags, filters, vacation auto-reply, and HTML composition in a responsive Material Design layout.
  • Shared Calendars
  • Multi-user calendar support with free-busy lookups, event invitations via iMIP, resource booking, delegation, and per-user ACL permissions for organizational scheduling.
  • Address Book Management
  • Personal and shared address books with contact groups, LDAP directory integration, vCard import and export, and CardDAV synchronization across all connected clients.
  • Resource Booking
  • Meeting rooms and equipment reservation with automatic conflict detection, approval workflows, and visibility controls for organizational resource management.
  • Thunderbird Integration
  • Official SOGo Connector extension provides seamless calendar and address book synchronization with Mozilla Thunderbird without manual CalDAV or CardDAV endpoint configuration.