Techniques described herein, which may provide for a location determination of a mobile device, can also provide for the determination of a viewing direction of a user of the mobile device. In particular, a user can wear a head-mountable apparatus with one or more light sensors configured to detect light from one or more modulated light sources. Using this information, not only may a location of the head-mountable apparatus be determined, but also an orientation, which can enable a determination of an approximate direction the user is looking.