How London Underground Gates Manage Millions of Taps a Day

How do London Underground gates let millions of people tap in with Apple Pay, Google Pay or a contactless card, and open in about half a second, before your bank has even said yes? Here's how TfL contactless payments really work: - Why Tube gates can't wait for your bank - The secure chip in your phone and its "stand-in" card number - Why tapping in with your phone and out with your card can mean two maximum fares - How every journey becomes one payment overnight, with the daily cap applied - What happens when a card can't pay, and the deny list Every day, millions of taps across the London Underground work this way. Next time you walk through a Tube gate, you'll know what's really happening in that half second. Follow Binaryhood for more on how the tech you use every day actually works. #LondonUnderground #TfL #Shorts #tech