Abstract: An apparatus for controlling a cursor (10) on an electronic viewing screen (102) connected to a computer (104) without using hands. The apparatus comprises a detecting unit (108), intended to be carried by a user (106). The detecting unit (108) is provided with at least one ultrasonic device (110), which emits ultrasonic signals mainly in a direction towards the user's (106) mouth cavity and registers reflected ultrasonic signals. The apparatus further comprises a processing unit (116) for transforming the reflected ultrasonic signals into control signals intended to control the cursor (100). Thereby, the control signals create movement or activation of the cursor on the viewing screen such that different conditions in the mouth cavity are associated with specific cursor commands.