An apparatus for performing data entry by a user includes a first electronic device configured to be attached to a person's head and including a display for viewing by the person; and a second electronic device configured to be attached to a person's forearm and used in combination with the first electronic device. The first and second electronic devices are configured for wirelessly communications with each other, at least some of the wireless communications representing user input by the person for interfacing with a user interface displayed to the person on the display of the first electronic device, whereby data entry by the person is accomplished. The first electronic device is configured to wirelessly transmit data entered by the person to a computer system for electronic storage in a non-transitory computer readable medium.