Baïkal is a lightweight CalDAV+CardDAV server. It offers an extensive web interface with easy management of users, address books and calendars. It is fast and simple to install and only needs a basic php capable server. The data can be stored in a MySQL or a SQLite database. It is compatible with iOS, Mac OS X, DAVx5 on Android, Mozilla Thunderbird and every other CalDAV and CardDAV capable application.