Instead, it relies on an ultrasonic distance sensor to detect a hand (or foot) waved in front of the door. An Arduino Leonardo runs the show, sounding a buzzer when the ultrasonic sensor is triggered.

Over the past few years we've seen one quite significant difference between Android phones and the iPhone: biometric authentication methods. While iPhones - since the iPhone X - have all used advanced ...

Redmi, a Xiaomi spin-off phone brand, says it has made in-display fingerprint sensors that work with LCD screens. Previously, only OLED screens supported them.