A controller device (209) is enabled to provide a virtual user interface of an electrical device (201) to be remotely used and to generate control messages (241) for controlling the electrical device by providing the controller device with a proxy (211) of the electrical device. The proxy is a movable software package which can be used for representing the electrical device in the controller device. The proxy can be configured to have a limited time-to-live in the controller device and/or a surrounding system may have been arranged to send to the controller device a proxy removal message when the corresponding electrical device is leaving the system or a data transfer connection to it has otherwise been lost. Therefore, a sufficiently up-to-date awareness of the electrical devices and a capability of remotely using them can be maintained in the controller device.