https://www.vice.com/en_us/article/k7ekmv/facebook-facial-recognition-app

Facebook developed an internal facial recognition app that allowed users to scan peoples' faces and identify them. Images obtained by Motherboard now show what that app looked like.

Business Insider first reported the existence of Facebook's facial recognition app in November last year. The app, made between 2015 and 2016, was available to Facebook employees and was designed to recognize employees and their Facebook friends who had facial recognition settings enabled, Facebook told Motherboard. Facebook uses facial recognition for spotting users in photos uploaded by themselves or others.