Like A Super Hero

Aside from being pleasurable, it's also more efficient. In most other (non-zoom) map programs, such as Yahoo or Google Maps, the screen refreshes itself as you enlarge your target, meaning you must reorient yourself at each step—the move from country- to city- to building-level isn't fluid. It happens quickly, but the brain loses its bearings over and over again, and has to readjust. On the other hand, "seamless zoom allows you to easily comprehend the spatial scale and relationship," Hanke says. Immediately and intuitively, you comprehend the distance between Mumbai and Hong Kong, or the size of the Eiffel Tower relative to a skyscraper.

Although the idea sounds uniquely suited to larger screens that can display many items at once, a zooming interface would mean that any Web page or document could fit comfortably on even the smallest screens. Today, most mobile devices strip down a Web page into its simplest elements, mostly text and a smattering of photos—there's no attempt to replicate the real page. A zoom system could display the whole shebang, even on a Nokia, to give you a sense of the full page before you magnify the text to a readable level. On traditional screens it would make information more accessible. Instead of remembering a complicated file path to find your virtual jar of honey, you could easily scan your screen for a graphical representation, then zoom down into it. Organizing information spatially makes it easier to remember. (You don't have to memorize every street name on your morning commute.) Search results, mapping, Web browsing—all these commonplace and essential tasks could potentially be done better by making them more visual and adding a bit of zoom to them.

Apple was the first to discover mobile devices as a venue for zooming interfaces. When you open a page on the iPhone, you see it in its entirety, which gives you a sense of how all the elements fit together. By sliding open two fingers on the screen, you zoom into any element, magnifying text to a readable level or looking more closely at a picture. As a result, iPhone users aren't scrolling through a seemingly endless column of links and text bits, as users of other mobile devices have to do.

The power of this idea isn't lost on other cell-phone developers. Microsoft, for instance, is developing its own zooming Web browser for mobile devices, called Deepfish. It operates a lot like the iPhone, displaying sites exactly as they would appear on a larger screen, and allowing you to drill down into the details, albeit with a joystick instead of your fingers. (A prototype was released in the first half of 2007.) ZenZui, the phone interface being developed by San Giovanni, the former Microsoft researcher, uses zooming to navigate between colorful tiles that display the weather, stock quotes and other data.

On larger screens, which hold more information, a zoom interface would boost productivity. By making better use of human spatial memory, it plays to our strengths, bringing "the full power of your visual system to bear on processing information," says Aguera y Arcas. Users can handle more tasks at once. Instead of struggling to manage a half-dozen open browser windows, with zoom our brains might be able to keep track of 50 to 100 items—a tenfold improvement.

Aguera y Arcas started working on the zoom idea as a graduate student at Princeton, and in 2003 founded a company, then named Sand Codex (later changed to Seadragon). Microsoft, well aware of the potential of zoom interfaces, acquired the company in 2006. Seadragon is an application for interacting with images, graphics and documents. Most images are encoded in reading order, from left to right, meaning you have to download a picture in its entirety before you can make sense of it, even if you want just a small piece. Seadragon, on the other hand, starts downloading everything at once, but it downloads only the bytes that you're viewing at any given moment. (If you're staring at a picnic scene, for instance, there's no reason to download the data that reveal the ants crawling across the blanket unless you zoom in close enough to see them.) This makes for speedy downloads, even with huge images, and allows for seamless zooming. It's a digital librarian's dream.