An #adversarial device that could detect if someone is a large cloud-connected beacon and a #privacy horror approaching you. Where you could say "Turn off your devices and we can have a nice time". Dunno if that's technically feasible, and its similarly socially awkward.
Another angle is regulation. Making #surveillance#spyware packaged as neat fun gadgets forbidden. But #governments are limping miles behind the bleeding edge, and have agencies that are salivating by all this.