Facebook is beginning to roll out an opt-in feature called "Nearby Friends," which enables users to see the physical location of their friends. (Facebook)


Facebook is rolling out a new tool that allows its users to track their friends in real time.

Flipping on the feature in the Facebook mobile app lets you share your general or specific location with friends. The idea is to make it easier to set up spontaneous coffee dates with friends or to let a worried parent know when you have arrived at your destination.

Sure, it sounds a little creepy. But the good news is that Facebook knows that being able to see exactly where your friends are at any time isn't a feature that everyone wants. And so it has built a couple of key features into the app to make sure that users can control who's seeing their information, when they can see it and how specific the information is.

And, perhaps most importantly, the whole service is opt-in.

That means that Facebook users won't have to turn it on at all if they're not interested in sharing their location or seeing where their friends are. If you don't want to use it, it will just be an option on your regular account settings that you never open.

The tool grew directly from Facebook's 2012 acquisition of Glancee, a startup that aimed to let people meet strangers who might share their same interests. As the product evolved, said Facebook product manager Andrea Vaccari (a Glancee co-founder), it became apparent that people were more interested in using the app to meet their friends, rather than more casual acquaintances or strangers.

"Even though it is kind of cooler to know about people you don't know, it's more valuable to know about friends," Vaccari said. "We really focused on the scope of the product to make it just about the people you care about."

To that end, Facebook has actually designed a lot of obstacles to stand between you and an accidental location disclosure. For one, similar to dating apps such as Tinder, the tool won't share your exact location, but rather lets you know when people are in the vicinity. In most cases, Nearby Friends displays the city or neighborhood a user is in, such as "Northwest DC," rather than showing your face on a map.

Only friends that have mutually agreed to see each others' information will show up in the feature.

"If you can see them, they can see you," Vaccari said, noting that this helps to eliminate icky "lurker" scenarios, where someone doesn't know another person can see their location.

To display your exact location to anyone, both you and your friend have to mutually agree to share location information. Then you can opt to take the extra step to show your precise location. Plus, you can choose to set a time limit on that disclosure. So, if you want to meet your friend sometime in the afternoon, you can share your location for a few hours only in order to facilitate a meet-up. If you decide you don't want to share your location at any time, you can just flip the switch on the feature.

"With many other products it's just a map and puts all your friends on there," Vaccari said. "Frankly, that's easier to build and there's a wow factor. But if you think about it, there are many, many times when it's not valuable to see if your friend is in one building versus in another building.  And for others, it's annoying or even frightening."

Additionally, Nearby Friends is only going to be available to Facebook users who report that they're 18 or older, and is designed so that only a user's friends are ever able to see the location information. There is no option to make your location available to the public, or even to your extended "friends of friends" network. And, if you want, you can use Facebook's existing friends group filters to share information with just a handful of people, such as your closest friends or your siblings.

"I think they’ve taken a reasonably conservative approach," said Jules Polonetsky, executive director of the Future of Privacy Forum, who was asked to add his input to the feature's design.

He said that Facebook's approach could make location-sharing more palatable to its broader audience "Location-sharing, to this point, has really been for early adopters," he said.

Facebook already occasionally collects users' locations, if they allow it, for posts where they "check-in"  to broadcast their location on their profile pages. Nearby Friends obviously collects more data, and more detailed data, but the bulk of that is only visible to the individual user. And, you can delete those data logs at any time in your settings, Vaccari noted.

Part of the reason the feature collects so much data, he noted, is to keep it from getting spammy. Users wouldn't want notifications that their roommates, for example, are in their neighborhood — at least, most of the time.

"We really worked hard to improve certain core aspects of the product, like how to be informative enough to avoid being too informative," he said. "We worked hard on notifications to make sure only notifications that popped up were really relevant."

Notifications that seem less important, he said, will show up in your News Feed, rather by way of a push notification.
The cautious approach Facebook's taking here seems to be part of a larger shift for the company, Polonetsky said, as it tries to recuperate a poor reputation on privacy and persuade users to trust it with an increasing amount of personal information.

"It's the right thing to do. But it's also necessary if I'm going to have Facebook help me with managing broader aspects of my life. Users need to be comfortable."

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