Chinese smartphone maker Xiaomi has become the latest to be linked to 3D face recognition technology for mobile authentication.Tech media has reported that Xiaomi's own facial technology is set to debut in the fourth quarter of this year in the expected flagship Mi Mix 2.Apple is supposedly testing a new 3D facial recognition technology for its upcoming handset.Meanwhile, Qualcomm yesterday announced advances in depth-sensing camera technology aimed at improved biometric authentication.A trial is in also underway in Britain that uses face recognition to authenticate railway passengers.