The invention provides a control device with transformable surface topology. The control device includes an input mechanism having an actuation surface that is configurable by a user between at least two different surface topologies. In a first configuration, the surface topology may provide a first shape for receiving user input and in a second configuration provide a second shape for receiving user input. The actuation surface in one example includes the upper surface of an input pad having a plurality of input arms and the upper surface of a fill pad having a plurality of fill tabs. At least one of the input pad and the fill pad may be moved in a direction of an axis perpendicular to the face of the control device to change the distance between the upper surfaces. The actuation surface in one example is rotatable to cause translation of at least one of the pads in the direction of the perpendicular axis.