Hundreds of Apps Can Listen for Marketing ‘Beacons’ You Can’t Hear Ifeadi C. 04:12 WIRED, Zero Tech Blog So-called ultrasonic beacons are becoming even more popular with marketers. Here's how to shut them out. The post Hundreds of Apps Can Listen for Marketing ‘Beacons’ You Can’t Hear appeared first on WIRED. via Zero Tech Blog Share this Share on FacebookTweet on TwitterPlus on Google+