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Android Apps Are Using Ultrasonic Tones to Track Customers

* More than 230 Android apps use ultrasonic technology to track customers
* Apps are able to listen to these silent signals through your phone’s microphone
* These ultrasonic tones are always on and impossible to hear

Your apps may be using your phone’s microphone to secretly listen to inaudible beacons from advertisements in billboards, websites and even brick-and-mortar shops. The technology is called ultrasonic tracking, and more and more apps are starting to use it without your permission.

New research from the European Symposium on Security and Privacy found that more than 230 Android apps currently incorporate this type of secret ultrasonic technology. Once an app is able to pick up on these silent beacons, it can then use those tones to feed marketers potentially private information, including your shopping habits and physical location.

Because mobile microphones are able to “hear” without being connected to WiFi, this means your apps are listening for these beacons all the time. Not only that, having these beacons continuously broadcasting also significantly increases the risk of incidental data collection.

It’s quite possible for a third-party to intercept these beacons and potentially use this information for personal profit. But perhaps even more concerning, is that researchers say these ultrasonic trackers can potentially de-anonymize people who pay for items using Bitcoin.

However, there are some ways to protect yourself and your data from this threat. In order for the ultrasonic beacons to work, these apps need permission to access your phone’s microphone. Take a few moments to assess which services your apps are able to access. For instance, it makes sense that Skype would need access to your phone’s microphone, but a free gaming app? Not so much.