Roundcube’s calendar lets you manage your appointments. The calendar supports all basic features, including recurring events.
The calendar interface uses two panes. On the left is a list with calendars, and on the right you see the actual calendar. There is one calendar (“Default”) created by default, but you can create, add and remove other calendars by clicking on the three vertical dots at the top of the calendar pane.
You can create a new event either via the Create button or by clicking in an empty field in the calendar. You can enter as much or as little information as you like (only the “summary” and date are required). If you want you can set up a reminder, make the event a recurring event and invite participants.
To edit an existing appointment, simply click on the entry. You will see a summary of the event with the option to edit or delete the event.
Roundcube’s calendar uses the iCalendar format. This is an open standard, which means that it is easy to import and export your calendars. For instance, if you use Outlook or the Calendar app on macOS then you should have no issues moving calendars to and from those applications.
To import or export events, simply click on the relevant button above the calendar. If you want to export just a single event then you can instead click on the event and select Options » Download. This will download an ics file, which you can then import in another calendaring application.
There are a dozen or so calendar preferences you can tweak under Settings » Calendar. Among others, you can change the default “week” view to something else, change the range of hours shown by default and manage categories.