If FaceID is anywhere near as quick and flawless as Apple claims, I want to see the UK government replace the biometric data on my passport with the data from a scan and then use FaceID tech to let me breeze through passport control without even pausing to insert my passport into a slot. The slot would only really be needed as a fail-safe mechanism. Imagine how quick entering the US could be… the self-service customs machine could verify your identity (they got the info before you left your home country) and have your slip ready by the time you walked up to the machine.