If you're using an Android phone that's less than three years old, it could be broadcasting the names of every Wi-Fi network you've connected to. A new investigation from the Electronic Frontier Foundation traced the behavior to a feature called Preferred Network Offload (PNO) introduced with the Honeycomb OS. As part of the phone's ongoing search for Wi-Fi connections, PNO periodically blasts out a list of named networks the phone has previously connected to, often while the phone is still in sleep mode. If the names include specific places, like "Verge HQ network" or "Nilay's Apartment," that list could potentially give away a person's movements and activity. But if you're worried about the leak, it's easy to fix. 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.