Through the feature you could know which of your friends, online, are near your position.
The company calls the feature “Find Friends Nearby,” and on Monday it was available through Facebook’s mobile apps and website despite the fact that it hasn’t been formally announced.
Being dubbed as a “stalking app” because it could open people up to potentially awkward or threatening interactions with strangers on the social network who know you’re nearby.
It appears that Facebook users must opt in to the feature by going to that site, otherwise their profiles will not appear in a list of people who are nearby.
Facebook developer Ryan Patterson, who says he developed Find Friends Nearby, hopes the app will be used in a bit positive way.
“For me, the ideal use case for this product is the one where when you’re out with a group of people whom you’ve recently met and want to stay in contact with. Facebook search might be effective, or sharing your vanity addresses or business cards, but this tool provides a really easy way to exchange contact information with multiple people with minimal friction.”