Remember when only a few people had mobile phones. Generally regarded as an object of derision, you would occasionally see business types clutching those ridiculous grey bricks to their faces and mutter to yourself 'what a prick.' Nowadays, an eyebrow hardly even flutters when we see a ten-year-old child happily texting away. You probably wouldn't notice anyway; you'd be too busy downloading an app that could definitively pinpoint who it was that had just farted in your tube carriage.