Citadel
All-in-one groupware, mail and collaboration server
Citadel is a mature, all-in-one collaboration suite that integrates email, calendaring, address books, instant messaging, and bulletin boards. It is designed for easy installation and minimal maintenance.
Key features
- Integrated mail and calendar
- Built-in groupware web client
- Instant messaging and forums
- Easy installer
Pros & cons
Strengths
- Single-package setup
- Low resource needs
Trade-offs
- Niche project
- Old-fashioned UI
Citadel replaces
Compare Citadel
47 head-to-head comparisons.
- Citadel vs Calcom Calendar
- Citadel vs Nextcloud
- Citadel vs Docker Mailserver
- Citadel vs Mail-in-a-Box
- Citadel vs Stalwart Mail Server
- Citadel vs mailcow
- Citadel vs CryptPad
- Citadel vs Mailu
- Citadel vs ONLYOFFICE Docs
- Citadel vs Maddy Mail Server
- Citadel vs Mox
- Citadel vs Rallly
- Citadel vs Colanode
- Citadel vs Radicale
- Citadel vs Easy!Appointments
- Citadel vs Collabora Online
- Citadel vs Baïkal
- Citadel vs OnlyOffice Community Server
- Citadel vs SOGo
- Citadel vs WildDuck
- Citadel vs Twake Workplace
- Citadel vs iRedMail
- Citadel vs ZenTao
- Citadel vs Nextcloud Deck
- Citadel vs Cozy
- Citadel vs Dovecot
- Citadel vs Nextcloud Groupware
- Citadel vs Apache James
- Citadel vs Twake Drive
- Citadel vs Exim
- Citadel vs Davis
- Citadel vs Openmeetings
- Citadel vs LibreOffice Online
- Citadel vs Cyrus IMAP
- Citadel vs Postfix
- Citadel vs Calligra Suite
- Citadel vs EGroupware
- Citadel vs Group-Office
- Citadel vs Horde Groupware
- Citadel vs DAViCal
- Citadel vs Kolab Groupware
- Citadel vs Kontact
- Citadel vs Feng Office
- Citadel vs Kopano Groupware Core
- Citadel vs Tine
- Citadel vs Courier Mail Server
- Citadel vs Cozy Contacts
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