At the Sodaq event in Hilversum a few weeks ago, I remember talking to someone who had written some code on the ESP8266 that counts the number of nearby Wifi stations (i.e. people with mobile phones) and relays the metric via LoRaWAN. The idea being that the device would report a metric showing the relative density of people in a given area.
While there seems to be lots code out there that finds Wifi APs, I can not find any code that finds stations. I also saw the following youtube video (https://www.youtube.com/watch?v=GQMZg5FPE watch 2:00-3:00) indicating that the ESP libraries in arduino allows for some basic snooping of Wifi stations.
Any pointers to whoever wrote this code or even a github link would be greatly appreciated.