A portable device such as a mobile phone, comprising a display screen, an input interface having a plurality of activable elements and processing means in connection with the display screen and the input interface, wherein the value of at least one parameter of the device can be changed by means of the input interface, characterized in that the device is arranged for displaying on the display screen a plurality of parameters representations, each one of these parameters representations including: an identification of the parameter; and an indication of what particular activable element or elements are to be used for changing the value of the parameter.