Rainlendar has small space and memory requirements and a customizable user-interface (using skins). The calendar can be placed on the desktop and can be managed using the Windows notification area. It has common functions such as task list and a reminder alarm. Different event types can be represented with different symbols.[2] Calendars can also be imported or synchronized using common file formats such as Outlook, iCal, and iCalendar files (using a plugin).[3][1]
In addition to the stand-alone calendar program, Rainlendar-server is available for Windows and Linux, which can synchronize distributed Rainlendar applications. The program can also be used as a LiteStep plugin.