United Kingdom: As I stand squashed on a crowded London commuter train, the screens of my fellow passengers flicker with a mesmerising glow. It’s a chilly Monday morning, but their faces are bathed in the warm light of their mobile devices.

As I stand squashed on a crowded London commuter train, the screens of my fellow passengers flicker with a mesmerising glow. It’s a chilly Monday morning, but their faces are bathed in the warm light of their mobile devices.