Good things in small packages

We rely on our mobile devices for an almost comically long list of functions: talking, texting, Web surfing, navigating, listening to music, taking photos, watching and making videos. Already, smartphones monitor blood pressure, pulse rate, and oxygen concentration, and before long, they'll be measuring and reporting air-pollutant concentrations and checking whether food is safe to eat. And yet we don't want bigger devices or decreased battery life; the latest Android phones, with their vivid 4.3-inch screens, are already stretching the definition of pocket size, to say nothing of the pockets themselves. The upshot is that the electronics inside the devices have to do more, but without getting any larger, using more power, or costing more.