In the current state of the art there are a number of operable devices 11, 12, 13 known that have an operating panel 14 through which a user of the device 11, 12, 13 can produce and/or change-existing operating states, Because of the fact that manual operation is often very complex and can also result in the distraction of the user in situations that require the full the attention of a user to be directed elsewhere, the invention increases the ease of operation and simultaneously reduces the amount of attention required to be paid to the devices 11, 12, 13. The invention uses a decision unit 15 that blocks or releases certain operating states of the operable device 11, 12, 13 based on the data received. The invention can be implemented, for example, so that a mobile telephone 11 installed in a vehicle 10 does not "transfer" any telephone calls or suppresses the making of telephone calls from within the vehicle 10 when the vehicle 10 is moving faster than a certain speed.