Earlier this week, Facebook announced that it’s testing a new feature in Australia called “Photo Magic” that will scan the Camera Roll of users’ phones for photos of their friends. If it finds the pictures, it will send you a notification and prompt you to send them to your friends via the Messenger app. Facebook chief of messaging David Marcus also said that the feature will likely be rolled out to the United States if the test period goes well.

How exactly does this work? The Facebook Messenger app will need permission to search your Camera Roll and use its facial recognition technology to cross-reference photos with the profiles of your Facebook friends. The idea behind the feature, small though it may seem, is to eliminate the seconds-long “friction” users encounter when they’re looking for photos to share.

Of course, users will be able to prevent the feature from identifying them by checking an option in the “timeline and tagging” section of Facebook’s settings. But how will users react to Facebook creeping on their pictures even off the site itself? While the tool will likely prove marginally helpful, the cost could outweigh the benefit for users concerned with their privacy.