How do you boost screen real estate on a smartphone without increasing the device's footprint significantly? You could add a pair of slide-out panels mounted behind the main display. But you wouldn't. We'd hope. Such a concept made its way out of LG HQ and into the hands of the United States Patent and Trademark Office, however, and three years after its submission date, the proposed device has returned to haunt the South Korean manufacturer, in the form of an issued patent. The concept in question is quite simple: a primary LCD would be visible at all times, and when the occasion called for another panel or two, they'd simpl
