A portable eye tracker device is disclosed which includes a frame, at least one optics holding member, and a control unit. The frame may be adapted for wearing by a user. The at least one optics holding member may include at least one illuminator configured to selectively illuminate at least a portion of at least one eye of the user, and at least one image sensor configured to capture image data representing images of at least a portion of at least one eye of the user. The control unit may be configured to control the at least one illuminator for the selective illumination of at least a portion of at least one eye of the user, receive the image data from the at least one image sensor, and calibrate at least one illuminator, at least one image sensor, or an algorithm of the control unit.