Electronic organiser (10) with a calendar (11) in which appointments at least according to date, time and an individual description, for example a person to be visited, are variable. If the organiser (10) is provided with an interface (22) which can exchange data in respect of the appointments with an interface (22) existing on another device (21), the data recorded in the calendar (11) can be used to run the other device or the electronic organiser (10) can be controlled by the other device. Thus for example data recorded in the calendar (11) can be used by a navigation system for faster input of the destination, or for example departure appointments can be changed by the other device according to the traffic or other situations.