The permanent networking of mobile devices can endanger the privacy of users and lead to new forms of monitoring. New technologies such as Google Nearby and Silverpush use ultrasonic sounds to exchange information between devices via loudspeakers and microphones.More and more of our devices communicate via this inaudible communication channel. Ultrasonic communication allows devices to be paired and information to be exchanged. It also makes it possible to track users and their behavior over a number of devices, much like cookies on the Web. Almost every device with a microphone and a loudspeaker can send and receive ultrasonic sounds. Users are usually unaware of this inaudible and hidden data transmission.
Researchers from the St Polten University of Applied Sciences in Austria has developed a mobile application that detects acoustic cookies, brings them to the attention of users and if desired, blocks the tracking. The app is, in a sense, the first available ultrasound-firewall for smartphones and tablets... more
