uXDT & Audio Beacons — Introduce your Paranoia to your Imagination, by Graham Penrose

Ultrasonic‍ cross-device tracking‍ (uXDT‍) apparently represents an apocalyptic threat to privacy‍ . The tech is being embedded in many apps but despite its significant intrusive abilities it is not complying — in most cases it would seem — with explicit consumer optin‍ / optout‍ choices. At best it is an underhand advertising trick, at worst it stands to become one of the alphabet agencies handiest IoT mass surveillance piggybacking collection methods for device ownership cross referencing and tracking. Have often do you opt-out?