A comparison of CalDAV and CardDAV implementations offers two overviews of client and server computer software implementations of the CalDAV and CardDAV protocols.
Client name | Platform | License | WebDAV ACL editor | Discovery of other user’s collections | ICalendar events | ICalendar tasks | ICalendar journals | ICalendar VAVAILABILITY (RFC 7953) | CalDAV Scheduling | CardDAV | vCard Synchronization | User interface | Online store | .well-known URLs | FBURL | DNS SRV | handles home-sets |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AgenDAV [1] | Cross-platform JavaScript Web browser | GNU GPL | Yes limited | No | Yes | — | Unknown | No | No Does not arrange meetings with participants | — | out of scope | AgenDAV's fullcalendar.io | No | No The used server is fixed in the configuration file | No Does not arrange meetings with participants | No the caldav-server settings need to be fixed in AgenDAV's configuration file | Yes |
Cadaver [2] | Command-line | GNU GPL | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
aCal [3] | Android | GNU GPL | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | — | Unknown | aCal | aCal | Unknown | Unknown | Unknown | Unknown |
AndroidCaldavSyncAdapater [4] | Android | GNU GPL | Unknown | Unknown | Yes | — | Unknown | Unknown | Unknown | — | out of scope | Android | Google Play | Unknown | No Out of scope | Unknown | Unknown |
CalDavZAP [5] | Cross-platform JavaScript Web browser | AGPL | No | No | Yes | Yes | Unknown | No | No Does not arrange meetings with participants | — | out of scope | CalDavZAP | No | No The used server is fixed in the configuration file | No Does not arrange meetings with participants | No The used server is fixed in the configuration file | Yes |
CardDavMATE [6] | Cross-platform JavaScript Web browser | AGPL | No | No | out of scope | out of scope | out of scope | out of scope | out of scope | Yes vCard 3.0 only | No | CardDavMATE | No | No The used server is fixed in the configuration file | No Out of scope | No The used server is fixed in the configuration file | Yes |
InfCloud (CalDavZAP+CardDavMATE) [7] | Cross-platform JavaScript Web browser | AGPL | No | No | Yes | Yes | Unknown | No | No Does not arrange meetings with participants | Yes vCard 3.0 only | No | InfCloud | No | No The used server is fixed in the configuration file | No Does not arrange meetings with participants | No The used server is fixed in the configuration file | Yes |
Chandler Desktop [8] | Cross-platform Python | Apache | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | No | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
DAVx⁵ [9] | Android | GNU GPL | No | No | Yes | Yes | Yes | out of scope | No (except attendees/invitations) | Yes | No (server always wins) | Android, OpenTasks | Google Play, OpenTasks | Yes | out of scope | Yes | Yes |
Tasks.org [10] | Android | GNU GPL | No | No | No | Yes | No | No | No | No | No | Android | Google Play | Yes | No | No | Yes |
jqCalDAV [11] | Cross-platform JavaScript Web browser | MIT | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | — | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
KCardDAV [12] (discontinued) | Cross-platform Kontact add-on | GNU GPL | Unknown | Unknown | — | — | — | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
KOrganizer, KAddressBook, Kontact | Unix-KDE | GNU GPL | Unknown | Unknown | Yes | Yes | Yes | Unknown | Unknown | Yes | Unknown | KOrganizer KAddressbook | KOrganizer KAddressbook | Unknown | Unknown | Unknown | Unknown |
Lightning [13] | Cross-platform Thunderbird Add-on | MPL, GPL, LGPL | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | — | Out of scope | Lightning | Lightning | Unknown | Unknown | Unknown | Unknown probably not |
CardBook [14] | Cross-platform Thunderbird Add-on | MPL | No | No | Out of scope | Out of scope | Out of scope | Out of scope | Out of scope | Yes vCard 3.0 and vCard 4.0 | Yes | CardBook | Mozilla Add-ons (ATN) | Yes | Out of scope | No | partial |
MineTime [15] | Cross-platform | Proprietary | No | No | Yes | No | No | No | No | No | No | No | MineTime | minetime.ai | No | No | No |
Mulberry [16] | Cross-platform | Apache | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Outlook CalDav Synchronizer [17] | Windows | AGPL | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | Yes | Unknown | Outlook | Unknown | Yes | Unknown | Yes | Yes |
pyCardDAV [18] | Cross-platform Python | MIT | Unknown | Unknown | — | — | — | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
The Bat! [19] | Windows | Proprietary | Unknown | Unknown | No | No | No | Unknown | Unknown | Yes | Unknown | The Bat! | The Bat!'s address book | Unknown | Unknown | Unknown | Unknown |
Inverse SOGo Connector-Integrator [20] | Cross-platform Thunderbird Add-on | MPL, GPL, LGPL | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Unknown | Yes | Unknown | Mozilla | Mozilla Add-ons | Unknown | Unknown | Unknown | Unknown |
Evolution | Cross-platform | GNU GPL | No | No | Yes | Yes | Yes | No | No | Yes vCard 3.0 only | Unknown | Evolution | Evolution | Yes | Yes if the URL does not require authentication | Yes | Yes |
ReminderFox [21] | Cross-platform Firefox | MPL 1.1 | Unknown | Unknown | Yes | Yes | Unknown | Unknown | No | — | Unknown | ReminderFox | Yes | Unknown | Unknown | Unknown | Unknown |
There are more clients, mentioned for completeness:
Server name | License | Programming language | RFC 2616 HTTP/1.1 | RFC 2617 HTTP auth. | RFC 2518 WebDAV | RFC 3253 WebDAV vers. | RFC 3744 WebDAV ACL | RFC 4324 iCal CAP | RFC 4331 WebDAV quota | RFC 4709 WebDAV mount | RFC 4791 CalDAV | RFC 4918 WebDAV ext. | RFC 5397 WebDAV current principal | RFC 5545 rev. iCal (Availability Check) | RFC 5546 iCal iTIP(Group Scheduling) | RFC 5689 WebDAV ext. MKCOL | RFC 5995 WebDAV POST add member | RFC 6352 CardDAV vCard | RFC 6578 WebDAV sync | RFC 6638 CalDAV sched.(Auto-Schedule) | RFC 7529 iCal RSCALE | RFC 7540 HTTP/2 | RFC 7809 CalDAV time zones by ref. | RFC 7953 iCal VAVAILABILITY | Free-busy URL |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Baïkal [22] [23] | GNU GPL | PHP | Yes [Note 1] | Yes | Yes | No | Some | No | No | No | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | No | Yes | Unknown | Yes [Note 1] | Unknown | Unknown | Yes |
Bedework [24] | Apache | Java | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Yes | Yes | Unknown | Unknown | Yes | Yes | Yes | Unknown | Unknown | Unknown | Unknown | Unknown |
Calendar and Contacts Server [25] | Apache | Python | Yes | Yes | Yes | Yes | Yes | No | Unknown | No | Yes | Yes | Yes | Yes | Yes | Yes | Unknown | Yes | Yes | Yes | Unknown | Unknown | Unknown | Unknown | Unknown |
Calypso [26] | GNU GPL | Python | Yes | Yes | Yes | No | Unknown | No | Unknown | No | Yes | Yes | No | Yes | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Cyrus IMAP [27] | BSD | C | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
DAViCal [28] [29] | GNU GPL | PHP | Yes [Note 1] | Yes | Yes | Yes | Yes | Yes | Unknown | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Unknown | Yes [Note 1] | Unknown | Yes | Yes |
DavMail [30] | GNU GPL | Java | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Fennel [31] | GNU GPLv3 | JavaScript | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Group-Office [32] | AGPL, proprietary | PHP | Yes [Note 1] | Yes | Yes | Unknown | Some | Unknown | Unknown | Yes | Yes | Yes | Yes | Yes | Unknown | Yes | Unknown | Yes | Unknown | Unknown | Unknown | Yes [Note 1] | Unknown | Unknown | Unknown |
Horde Groupware | GNU LGPL | PHP | Yes [Note 1] | Yes | Yes | No | Some | No | No | Unknown | Yes | Yes | Yes | Yes | Yes | No | No | Yes | No | No | No | Yes [Note 1] | No | No | No |
Nextcloud [33] | AGPL v3 | PHP | Yes [Note 1] | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Yes [Note 1] | Unknown | Unknown | Unknown |
Open Xchange | GNU GPL, CC | Java, JavaScript | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
ownCloud [34] | AGPL v3 | PHP | Yes [Note 1] | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Yes | Unknown | Unknown | Unknown | Yes [Note 1] | Unknown | Unknown | Unknown |
Radicale [35] | GNU GPL | Python | Yes | Yes | Some | No | Some | No | Unknown | No | Some | Some | Some | No | Some | No | Unknown | Some | Unknown | No | Unknown | Unknown | Unknown | Unknown | Unknown |
SabreDAV [36] | BSD | PHP | Yes [Note 1] | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Unknown | Yes [Note 1] | Unknown | Yes | Unknown |
SOGo [37] | GNU GPL | Objective-C | Yes | Yes | Unknown | Unknown | Some [38] [39] | Unknown | Unknown | Unknown | Some [40] [41] | Unknown | Unknown | Some [42] [43] [44] [45] | Unknown | Unknown | Unknown | Unknown | Some [46] | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Xandikos [47] | GNU GPL | Python | Yes | Yes | Yes | Some | Some | No | No | No | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes | No | Unknown | Yes | No | No | Unknown |
Zarafa | AGPL, proprietary | PHP | Yes [Note 1] | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Read only | Unknown | Unknown | Unknown | Yes [Note 1] | Unknown | Unknown | Unknown |
Zentyal [48] | GNU GPL | Perl | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown | Unknown |
Meishi [49] | BSD | Ruby | Yes | Yes'basic' | Someyes | Someno | Yesmuch of | No | Unknown | No | No | Unknown | Yes | No | No | No | Unknown | Some | Unknown | No | No | Unknown | No | No | Unknown |
Zimbra | GNU GPL | Java | Yes | Yes | Yes | Yes | Yes | No | Unknown | No | Yes | Unknown | Yes | Yes | Yes | Yes | Unknown | Yes | Unknown | Yes | Unknown | Unknown | Unknown | Unknown | Unknown |
The table is missing Kopano, Kerio Connect and Scalix, which are mentioned here for completeness.
Mac OS X Server is a series of discontinued Unix-like server operating systems developed by Apple Inc. based on macOS. It provided server functionality and system administration tools, and tools to manage both macOS-based computers and iOS-based devices, network services such as a mail transfer agent, AFP and SMB servers, an LDAP server, and a domain name server, as well as server applications including a Web server, database, and calendar server.
GNOME Evolution is the official personal information manager for GNOME. It has been an official part of GNOME since Evolution 2.0 was included with the GNOME 2.8 release in September 2004. It combines e-mail, address book, calendar, task list and note-taking features. Its user interface and functionality is similar to Microsoft Outlook. Evolution is free software licensed under the terms of the GNU Lesser General Public License (LGPL).
Microsoft Outlook is a personal information manager software system from Microsoft, available as a part of the Microsoft 365 software suites. Primarily popular as an email client for businesses, Outlook also includes functions such as calendaring, task managing, contact managing, note-taking, journal logging, web browsing, and RSS news aggregation.
WebDAV is a set of extensions to the Hypertext Transfer Protocol (HTTP), which allows user agents to collaboratively author contents directly in an HTTP web server by providing facilities for concurrency control and namespace operations, thus allowing Web to be viewed as a writeable, collaborative medium and not just a read-only medium. WebDAV is defined in RFC 4918 by a working group of the Internet Engineering Task Force (IETF).
SOGo is an open source collaborative software (groupware) server with a focus on simplicity and scalability.
A Service record is a specification of data in the Domain Name System defining the location, i.e., the hostname and port number, of servers for specified services. It is defined in RFC 2782, and its type code is 33. Some Internet protocols such as the Session Initiation Protocol (SIP) and the Extensible Messaging and Presence Protocol (XMPP) often require SRV support by network elements.
Calendaring Extensions to WebDAV, or CalDAV, is an Internet standard allowing a client to access and manage calendar data along with the ability to schedule meetings with users on the same or on remote servers. It lets multiple users in different locations share, search and synchronize calendar data. It extends the WebDAV specification and uses the iCalendar format for the calendar data. The access protocol is defined by RFC 4791. Extensions to CalDAV for scheduling are standardized as RFC 6638. The protocol is used by many important open-source applications.
Kolab is a free and open source groupware suite. It consists of the Kolab server and a wide variety of Kolab clients, including KDE PIM-Suite Kontact, Roundcube web frontend, Mozilla Thunderbird and Mozilla Lightning with SyncKolab extension and Microsoft Outlook with proprietary Kolab-Connector PlugIns.
EGroupware is free open-source groupware software intended for businesses from small to enterprises. Its primary functions allow users to manage contacts, appointments, projects and to-do lists. The project releases its software under the terms of GNU General Public License (GPL).
Z-Push is a FOSS implementation of the Microsoft Exchange ActiveSync protocol which is used to synchronize email, personal contacts and other items between a central server and a mobile device.
vCard Extensions to WebDAV (CardDAV) is an address book client/server protocol designed to allow users to access and share contact data on a server.
DAViCal is a server for calendar sharing. It is an implementation of the CalDAV protocol which is designed for storing calendaring resources on a remote shared server. Although the events are stored in a SQL database the information between client and server is transferred in the iCalendar format.
Exchange ActiveSync is a proprietary protocol by Microsoft, designed for the synchronization of email, contacts, calendar, tasks, and notes from a messaging server to a smartphone or other mobile devices. The protocol also provides mobile device management and policy controls. The protocol is based on XML. The mobile device communicates over HTTP or HTTPS.
sabre/dav is an open-source WebDAV server, developed by fruux and built in PHP. It is an implementation of the WebDAV protocol, providing a native PHP server implementation which operates on Apache 2 and Nginx web servers.
ownCloud, a Kiteworks Company, is a free and open-source software project for content collaboration and sharing and syncing of files in distributed and federated enterprise scenarios. It allows companies and remote end-users to organize their documents on servers, computers, and mobile devices and work with them collaboratively while keeping a centrally organized and synchronized state.
Shadowsocks is a free and open-source encryption protocol project, widely used in China to circumvent Internet censorship. It was created in 2012 by a Chinese programmer named "clowwindy", and multiple implementations of the protocol have been made available since. Shadowsocks is not a proxy on its own, but (typically) is the client software to help connect to a third-party SOCKS5 proxy. Once connected, internet traffic can then be directed through the proxy. Unlike an SSH tunnel, Shadowsocks can also proxy User Datagram Protocol (UDP) traffic.
Mailfence is an encrypted email service with a focus on security and privacy that offers OpenPGP based end-to-end encryption and digital signatures for usage in emails. It was launched in November 2013 by Belgium-based company ContactOffice Group, which has been operating an online collaboration suite since 1999.
Xabber is a XMPP client for the Android Operating System. It is developed as an open source Project on GitHub and is licensed under the GNU GPL v.3 license. The original developers are from a software company called Redsolution, Inc. Xabber is available on the Android Play Store and on F-Droid.
The JSON Meta Application Protocol (JMAP) is a set of related open Internet Standard protocols for handling email. JMAP is implemented using JSON APIs over HTTP and has been developed as an alternative to IMAP/SMTP and proprietary email APIs such as Google's Gmail and Microsoft's MAPI . Additional protocols and data models being built on top of the core of JMAP for handling contacts and calendar synchronization are meant to be potential replacements for CardDAV and CalDAV, and other support is currently in the works.