A mobile device and a method are provided. A mobile device includes a display, a sensor configured to sense a user operation with respect to the display, a fingerprint sensor configured to sense a fingerprint of the user that input the user operation, a storage configured to store preregistered fingerprint information, and a controller configured to perform an operation corresponding to the user operation when the fingerprint sensed by the fingerprint sensor matches the stored fingerprint information and perform a fingerprint registration operation when the fingerprint sensed by the fingerprint sensor does not match the stored fingerprint information.