Embodiments described herein may help to provide a lock-screen for a computing device. An example method involves: (a) displaying two or more rows of characters and an input region that is moveable over the rows of characters, (b) based on head-movement data, determining movement of the input region with respect to the rows of characters, (c) determining an input sequence, where the sequence includes one character from each of the rows of characters that is selected based at least in part on the one or more movements of the input region with respect to the rows of characters, (d) determining whether or not the input sequence matches a predetermined unlock sequence, and (e) if the input sequence matches the predetermined unlock sequence, then unlocking the computing device.
