On Monday, The New York Times published a story that showed just how easy it is to identify and locate people through anonymized data that's almost constantly being collected by apps on our phones.

While the information provided by the applications doesn't always identify the user, the location tracking is often so precise that it can be used to pinpoint an individual, since it shows where the person is at night (presumably at home) and where they go throughout the day. The Times says many apps use or sell this information to help target ads and for other purposes.

In recent years, Apple and Google have made it easier to identify the applications that have access to your information, and to turn off the ability for those apps to see where you are. Sometimes this can stop an app from performing correctly: a mapping application would need to know your location to provide you with accurate directions somewhere, for example. But others, like weather apps, don't necessarily need to know where you are at all times. You can always just search for your current location.

The iPhone also has controls that allow apps to use your location only when you're using them, instead of all of the time.

I recently went through my iPhone and was surprised to see that I had a few applications that were set to always track my location, instead of as needed. In this guide I'll show you how to take more control of the apps that know where you are, and how to turn off those that never should require your location at all.