Abstract: A data entry mechanism for a handheld computer is provided. The data entry mechanism comprises: a plurality of keys configured to be actuated by a stylus of the handheld computer, each of the plurality of keys being electronically coupleable to the handheld computer and generating an electronic signal upon actuation by the stylus; and an encasement structure to retain the plurality of keys, the structure being engagable with a slot of the handheld computer. The data entry mechanism may be used to facilitate data input to a computing or a telecommunications device.