<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Ok</div><div id="AppleMailSignature"> So here is a good read from the land of tinfoil hats and hacking air gapped openbsd laptops via sound.</div><div id="AppleMailSignature"><br></div><div id="AppleMailSignature"><br></div><div id="AppleMailSignature"><a href="http://arstechnica.com/security/2016/11/how-to-block-the-ultrasonic-signals-you-didnt-know-were-tracking-you/">http://arstechnica.com/security/2016/11/how-to-block-the-ultrasonic-signals-you-didnt-know-were-tracking-you/</a></div><div id="AppleMailSignature"><br></div><div id="AppleMailSignature">So the tldr parts , ad tracking via ultrasound beacons . Imagine you install the wallmart app to get the 25% off coupon but it's tracking you via ultrasound beacons. </div><div id="AppleMailSignature"><br></div><div id="AppleMailSignature">Interesting non the less .</div><div id="AppleMailSignature"><br><br>---<div>Mark Saad | <a href="mailto:mark.saad@ymail.com">mark.saad@ymail.com</a></div></div></body></html>