An explanation of the iPhone’s “Frequent Locations” feature, and instructions for turning it off if you don’t want it to track and correlate geolocation data this way. However, as this article points out, turning off “Frequent Locations” doesn’t erase the data your phone has already collected!

This phone feature is also a practical illustration of how a collection of data points can be used to automatically draw larger inferences about your habits and identify. For an interactive visualization of how this can be done, see our “Ready or Not?” educational app!