An integrated removable functional faceplate for a portable computer system. The removable functional faceplate employs specially located electrical contacts or pads that mate with similarly located electrical contacts mounted on the portable computer system, e.g., a personal digital assistant (PDA) or other electronic device. The electrical contacts of the functional faceplate carry signals that are responsive to the pressing of physical buttons which may be placed in any location on the functional faceplate. This allows individual faceplates to be developed that are specialized for a particular purpose, e.g., extended keyboards, adapted for gaming, adapted for music playing, etc. The functional faceplates may have specialized button types that are adapted for a particular use and are also located in custom positions that reflect the particular use employed. When the functional faceplate is removed from the portable computer system, it may have no buttons or it may provide a standard PDA button group. An identification circuit may be employed on the functional faceplate to indicate its button group and signaling characteristics. Alternatively, the functional faceplate may also include a data generation device, e.g., a global positioning system (GPS) or electronic thermometer, a music player, a smart card, etc. Alternatively, the functional faceplate may also include an auxiliary power supply.