How Does Google Know Where You Live? - LockerGnome
"If you have an Android device running 4.1 Jelly Bean or later, then you should know that having Google Now active on your phone gives Google all the data it needs to determine where you live whether you submit your address through the Google Play Store or not. Where you spend most of your time, log in to Google on your PC, and do the majority of your surfing is home. You might work somewhere 8-10 hours per day, and have an active night life, but there is a place your phone goes to charge and you go to sleep at the end of the day. After a few days’ worth of data, Google has a pretty good idea where home is."