Please be aware that the following packages are from unofficial repositories. That means they are not reviewed by openSUSE and may contain unstable or experimental software.
A CalDAV calendar and CardDav contact server
The Radicale Project is a CalDAV (calendar) and CardDAV (contact) server. It aims to be a light solution, easy to use, easy to install, easy to configure. As a consequence, it requires few software dependances and is pre-configured to work out-of-the-box. The Radicale Project runs on most of the UNIX-like platforms (Linux, BSD, MacOS X) and Windows. It is known to work with Evolution, Lightning, iPhone and Android clients. It is free and open-source software, released under GPL version 3.