Reactive Design

The announcement of Apple’s iOS 6 last week saw the first major outing of something I like to think of as “Reactive Design”: interfaces and applications that change their appearance and functionality not just to the dimensions or aspect ratio of a device but rather to the user’s activities and environment.

Reactive Design is enabled by modern devices’ ability to answer several key questions, including:

• Is the device moving? (using the accelerometer)
• Is the device travelling? (GPS data over time)
• Is the device in a significant location? (GPS data)
• How loud is the environment? (Microphone input)
• Is it bright or dark? (Light meter – proximity sensor)

With appropriate computation, applications or the underlying OS can extrapolate useful information about the user. Combining light readings, accelerometer, and GPS data we can know whether the user is running or in a moving vehicle, on the final stretch of their habitual run, or navigating an unfamiliar airport.

You can see basic elements of Reactive Design in Apple’s new app, Passbook:

“Passes appear on your Lock screen at the appropriate time and place — like when you reach the airport or walk into the store to redeem your gift card or coupon. And if your gate changes after you’ve checked in for your flight, Passbook will even alert you to make sure you’re not relaxing in the wrong terminal.”

There are, of course, opportunities to keep developing the experience. For example, the information hierarchy in the boarding pass, with its heavy emphasis on departure and destination airports, is helpful when flipping through multiple boarding passes or e-tickets some time before travelling. Approaching the flight, though, the names of airports being travelled between is perhaps less critical.

Pulling up to the airport, the screen might ideally emphasize the gate number, boarding time, and flight number; as the scheduled boarding time approaches, emphasis might shift to the boarding group information, and so on.

I’ll be posting more about Reactive Design in the coming weeks. I’d love to know how you feel about the subject, and what other opportunities do you see for apps Passbook to exhibit Reactive Design. Please comment!