Facebook recently introduced the discretionary “Nearby Friends” feature that allows you to track friends, proving that the company has not shifted from their fundamental competency of essentially enabling stalking. Facebook users can whether their precise location is revealed. This can mean that you will be able to track friends down to the half mile.

 
Unlike most Facebook services which request users to opt-out, “Nearby Friends” is a voluntary opt-in service. Other such opt-in features have proven problematic, such as the feature allowing for the automatic uploading of iPhone photos to Facebook.  “Nearby Friends” only works when two parties each turn on the service and if you choose to share the information regarding your location with them. According to Business Insider:
 
To prevent stalking, the function comes with a timer that switches off Nearby Friends after a certain time, for instance one hour. And only friends can see you in Nearby Friends — not friends of friends or members of the public you have not confirmed as friends.
Nearby Friends also produces an activity log, which you can delete at will. The log also produces maps of your whereabouts over time, which you can also delete if you want.
 

 
Facebook has attempted to get users to reveal where they are in the past, but they have not been successful in their efforts. The conception of Facebook Places, a feature similar to Foursquare, did not gain popularity. It was slightly more popular than Facebook Poke, which was a feature similar to Snapchat. Instagram has been experimenting with the use of Facebook Places:
 
When Nearby Friends is on, you can see when your friends are traveling if they’re also using this feature and sharing with you. You’ll be able to see the city or neighborhood they are in, including on their profile. When you see a friend visiting a place you’ve been, it’s the perfect opportunity to send a recommendation for a great restaurant. You can also make last-minute plans to meet up with a friend who happens to be in the same place you’re headed to.
 
This new feature is the result of an acquisition, much like Instagram, Oculus Rift, and WhatsApp. Facebook is attempting to become the next Google.  Andrea Vaccari, the former Glancee CEO who now works at Facebook, promises Business Insider that all of the information gathered through the “Nearby Friends” feature about exactly where you’ve been will not be sold for to generate revenue for Facebook.
 

 
Obviously, the new feature has the potential to produce a lot of new data on users. Facebook product manager Andrea Vaccari says that, currently, none of that data will be used for purposes outside the app. It will not be used to help target advertising, for instance. And Nearby Friends will not be usable by business Pages that you’re fans of — so local restaurants and stores won’t be pinging you with offers when you walk by. (Of course, given Facebook’s track record, it would seem natural that such a useful new trove of location data might eventually be monetized in some way in the future.)
 
The operative word there is “currently.”