How do they get wifi or bluetooth to extend to (1k/3,200ft) when standard wifi or bluetooth is less than 400ft? Are they taking control of the wifi chip and making it so the packets are allowed to take much longer to arrive to cover the greater distances?
Simply by using the phone's GPS and sending all messages to a centralized server which then broadcasts it to the "in the area" participants.
Much less interesting now compared to actual proximity apps.