This is part of IEEE Spectrum's special report: Top 11 Technologies of the Decade
Douglas Adams's Hitchhiker's Guide to the Galaxy series is named after a pocketable device that contains everything worth knowing. But that seems almost quaint today, when you can carry the full contents of the Web in your pocket, as well as a telephone, a camera, a radio, a television, and a navigation system. Today's smartphones are marvels of engineering, crammed with more features than the average PC. They've become the prime driver of innovation for both software and hardware.
It took half a century to shrink the mainframe from the size of a living room to that of a suitcase. It took another decade to make it smaller than a wallet. The smartphone has swallowed and assimilated functionality from music players, remote controls, gaming consoles, even printed maps and news publications. And now that smartphones are serving as Wi-Fi hot spots, they can replace wireless routers and modems, too. Smartphones are becoming as essential as keys or a wallet, and they'll soon replace those as well.
This has some real consequences. Unlike its predecessors, the smartphone is an inherently personal device: Not only is it always on, it's always somewhere on us. Without realizing it, we've let smartphones usher us into an age of ubiquitous, pervasive computing that technologists, as well as science-fiction authors, have been dreaming about for years [PDF].
"Smartphones help users stay connected to information at any given time, any given location," says Dilip Krishnaswamy, a Qualcomm engineer and associate editor in chief of IEEE Wireless Communications. "The information is just there when you need it."
We've come to rely on such connectivity. There's no need to pack a map or directions when an app can guide you in real time, nor to consult a restaurant guide before leaving the house. In these and a thousand other ways, the smartphone, more than any other technology to have emerged in the past decade, is the one that has most changed our lives.
To be sure, back in 1973, Motorola's Martin Cooper didn't set out to build an always-connected, portable computing device. He was simply trying to shrink the car phone down to the size and weight of a luggable brick. But once the cellphone had earned a permanent place in our pockets, it became an unavoidable platform for innovation, upstaging the PC. If Starbucks wants to make it quicker and easier to pay for a cup of coffee, why not do it through the phone? If The New York Times wants to get away from paper, well, everyone's already carrying around a perfectly readable screen.
Smartphones are more than just bells and whistles—they actually change behavior. With a traditional mobile phone, users spend most of their time making calls and sending text messages. On a smartphone, basic communication takes a back seat to Internet browsing, e-mail, entertainment, and games. This difference is due to three key ingredients, each of which has seen tremendous advances in the last decade: hardware, software, and network infrastructure.