Your Android phone is a SNITCH: Wi-Fi bug makes you easy to track Your Android phone is a SNITCH:

Your Android phone is a SNITCH: Wi-Fi bug makes you easy to track Your Android phone is a SNITCH:
Wi-Fi bug makes you easy to track Even asleep, your mobe could be blabbing your every move
By Neil McAllister, 3 Jul 2014
 
Your mobile device could be compromising your privacy by broadcasting your location history over the air, even when it is in sleep mode, according to new research by the Electronic Frontier Foundation. Of particular concern are newer Android gadgets, specifically those running Android 3.1 "Honeycomb" or later. That version of the Google OS introduced a feature called Preferred Network Offload (PNO), which has a habit of broadcasting the names of the last 15 Wi-Fi networks a device has joined, even when the screen is off.
 
The idea is to conserve battery by allowing a phone to connect to known Wi-Fi networks even while in sleep mode, since Wi-Fi uses less power than the mobile data radio. The problem, the EFF says, is that your wireless network history can give a worryingly accurate and thorough picture of your movements.
 
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