The SoniControl project of St. Pölten University of Applied Sciences 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 thus, in a sense, the first available ultrasound-firewall for smartphones and tablets.

"The most challenging part of developing the app was to devise a method that can detect different existing ultrasound-transmission techniques reliably and in real time", said Matthias Zeppelzauer, Head of the project and Senior Researcher in the Media Computing research group of the Institute of Creative\Media/Technologies at St. Pölten UAS.

This makes it possible to track the user's behaviour across multiple devices, and relevant user profiles can be merged with one other.

In this way, more accurate user profiles can be created for targeted advertising and filtering of internet content.

Only a permanent deactivation of the microphone would help, whereby the device as a telephone would become unusable.

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