There is disclosed a computing apparatus including a first context within which first processing activity may be performed and a second context within which second processing activity may be performed independent of the first processing activity, the apparatus further may include input and/or output channels with which the first and second contexts may communicate and a switch function operated by a selector; whereby operation of the selector by a user selectively allows communication between the first context and/or the second context (of the first part) and the input and/or output channels (of the second part). An indicator is provided to indicate which context is in communication with the input/output channels.