Incidentally he has named the extension as Marauders Map after the fictional map by the same name in the J.K.Rowling masterpiece series, Harry Potter. The Harry Potter series contains a magical Marauder’s Map which reveals the whereabouts of any person to the owner of the map. It is a open secret that Facebook stores and shares FB users data with friends and the data is very accurate so using this extension, you can check on the locations of any Facebook friend with ease. The Marauders Map retrieves the location data from messages sent through Facebook Messenger for Android and iOS therefore those who have enabled location services on their iPhone or Android phone are susceptible to this location hack. The Marauders Map can be used to find out a Facebook friends location from the past also. However, as said above, only if you are using the Facebook Messenger App for iOS and Android with location enabled, can the Marauders Map capture location details. If you don’t want to share your location with your Facebook friends or keep your location data private, you should disable location sharing feature by tapping the arrow icon in your Messenger. The best option is to disable the Facebook Messenger Apps location access altogether from the device settings.