Pry-Fi is an app which according to it makers "will prevent your device from announcing all the networks it knows to the outside world, but it will still allow background scanning and automatically connecting to Wi-Fi networks. While you are not connected to a Wi-Fi network, the MAC address will constantly be pseudo-randomized, following a pattern that still makes the trackers think you are a real person, but they will not encounter your MAC address again. This will slowly poison their tracking database with useless information."

 

Pry-Fi will randomize your MAC address every time your device connects to a WiFi network. The app requires root access and will work on devices with android 4.2 and up.

Pry-Fi will secure your privacy to some extent because there are still many ways to get the job done. 

Download: Google Play