Facebook announced today it will be rolling out a new social feature to its mobile app called Nearby Friends. The feature allows Facebook users to occasionally receive notifications when common friends are in similar locations similar to features offered by Foursquare and Apple’s Find My Friends service.

If you turn on Nearby Friends, you’ll occasionally be notified when friends are nearby, so you can get in touch with them and meet up. For example, when you’re headed to the movies, Nearby Friends will let you know if friends are nearby so you can see the movie together or meet up afterward.

In its announcement, Facebook emphasizes that the location sharing feature is opt-in meaning users will have to actively decide to turn on the feature rather than the social network flipping the feature on for everyone.

Nearby Friends also supports the ability to manage which groups of friends the features recognizes, and you can disable the feature at any point of course.

Similar to Apple’s Find My Friends app, Facebook’s Nearby Friends service offers granular controls for sharing precise locations for a set duration. Unlike Find My Friends, it’s cross-platform.

Facebook says its opt-in feature will be rolling out to users in its existing iPhone app “over the coming weeks”.