A thermal imaging accessory (TIA) is linked with a head-mounted smart device (HMSD) with a data display for displaying data for an eye of a user wearing the HMSD. The HMSD supports the TIA in an orientation where a field-of-view of a thermal imaging camera of the TIA is substantially in alignment with the field-of-view of an eye looking through the data display. The HMSD is configured to: link the TIA to the HMSD, activate a thermal imaging application on the HMSD to receive data from the TIA and display it on an HMSD data display, receive thermal imaging data of a target from the TIA, process the thermal imaging data received from the TIA, and initiate a display of the processed thermal imaging data on the HMSD data display.