Large gatherings such as weddings and conferences can be socially overwhelming. Pressure to learn people's names only adds to the stress. A new facial-recognition app could come to the rescue—but privacy experts recommend proceeding with caution.

The app, called SocialRecall, connects names with faces via smartphone cameras and facial recognition, potentially eliminating the need for formal introductions. “It breaks down these social barriers we all have in terms of initiating the protocol to meet somebody,” says Barry Sandrew, whose start-up, also called SocialRecall, created the app and tested it at an event attended by about 1,000 people.

After receiving an invitation to download SocialRecall from an event organizer, a prospective user is asked to take two selfies and sign in via social media. At the event, the app is active within a previously defined geographical area. When a user points his or her phone camera at an attendee's face, the app identifies the individual, displays the person's name, and links to his or her social media profile. To protect privacy, it recognizes only those who have consented to participate. And the app's creators say it automatically wipes users' data after an event.

Ann Cavoukian, a privacy expert who runs the Privacy by Design Center of Excellence at Ryerson University in Toronto, commends the app's creators for these protective measures. She cautions, however, that when people choose to share their personal information with the app, they should know that “there may be unintended consequences down the road [with] that information being used in another context that might come back to bite you.”

The start-up has also developed a version of the app for individuals who suffer from prosopagnosia, or “face blindness,” a condition that prevents people from recognizing individuals they have met. (Sandrew, who has prosopagnosia himself, notes that the app has not yet been tested on others with the condition.) To use this app, a person first acquires an image of someone's face, from either the smartphone's camera or a photograph, and then tags it with a name. When the camera spots that same face in real life, the previously entered information is displayed. The collected data are stored only on a user's phone, according to the team behind the app.

Jason Schultz, a professor of clinical law at New York University, who was not involved with the app's creation, remains wary: “The cost to everyone whom you are surveilling with this app is very, very high, and I don't think it respects the consent politics involved with capturing people's images.”