If you are using Android Purchased before 2011, You data is " not safe "

Thoseof you who  are  using Android Mobile OS  phones  less that  3 years old,  that is  any Android phone purchase before 2011, Beware , it could be broadcasting the names of every Wi-Fi network you've connected to and in the process leak sensitive data  and compromise privacy 

According to findings by the Electronic Frontier Foundation,  which are reproduced across many tech websites   reveals that  Android device with Android 3.1 Honeycomb or later installed is in Preferred Network Offload mode, meaning it broadcasts the recent Wi-Fi networks it was connected to, allowing anyone within Wi-Fi range to figure out exactly where the user is based and where they have previously been.

Howeeve these no need to panic   There always a solution, as people who  use technology products are more often than not smarter than who makes them

 Just go to "Advanced Wi-Fi" settings and disable the "Keep Wi-Fi on during sleep" option to stop PNO from checking for networks in sleep mode.  

Acording  to TheVerge Devices running iOS 6, 7, or 8 are not affected by the bug, although EFF reported some data leakage in iOS 5 devices.