Face ID is a biometric authentication system developed by Apple Inc. for its iPhone and iPad Pro devices, first released in November 2017 with the iPhone X. It uses facial recognition to unlock devices, authorize payments, grant access to sensitive data, and track facial expressions for Animoji and other features. On devices running iOS 18 or later, Face ID can be used to lock specific apps.
Face ID employs a TrueDepth camera to capture accurate facial data. This camera projects and analyzes over 30,000 invisible infrared dots to create a detailed 3D depth map of the user's face and also captures an infrared image. This data is then transformed into a mathematical representation and compared to enrolled facial data, all within the device's Secure Enclave. Apple claims that the probability of a random person unlocking your device using Face ID is less than 1 in 1,000,000. The system is designed to resist spoofing attempts using photos or masks, and it is also attention-aware, requiring the user's eyes to be open and directed at the device.