We are considering to add this feature to Yodeck.
Specifically, you will need to add a web camera or a Raspberry Pi Camera and use Google Coral, a USB AI module that does analytics and demographics of viewers. Total additional cost for hardware per screen would be something around $100. And you would get a) reports on number of viewers and demographics, b) triggers to change content based on demographic groups (e.g. ads targeting males over 50).
We love this feature, but, to be honest, it is a bit down the road, likely for Q1-Q2 2020. Hope you stay on board to see it getting released!