A highly portable wearable apparatus is provided to capture high-quality image data of eye movement used for eye-tracking. The wearable apparatus comprises a coupling member adapted to securely couple the apparatus to an eyewear frame, an arm assembly having a distal end and configured to enable vertical and lateral of movements of the distal end, and an imaging assembly disposed on the distal end. The imaging assembly, via vertical and lateral movements of the distal end, can be disposed in a position close to an eye of a user that is suitable for eye-tracking when the user wears an eyewear frame with the apparatus deployed thereon. The imaging assembly is configured to capture infrared-illuminated eye and wirelessly transmit captured image data. A configuration in connection with infrared source placement is provided to achieve optimal glint-tracking used to track head movement for improving quality of eye-tracking.
