Matias Duarte. (Rob Pegoraro/Yahoo Tech)

SAN FRANCISCO — Yesterday’s keynote at Google’s I/O developer conference marked Google’s debut of an ambitious venture into interface concepts called “Material Design.” Google’s Matias Duarte, a vice president of design at the company, introduced it with some fairly airy language: “What if pixels didn’t just have color, but also depth?”

A few minutes of onstage demos weren’t quite enough to get really deep with this, so I sat down with Duarte this morning. He began by describing Material Design as some sort of sentient entity: “It’s very considered in how it thinks about motion.”

In plainer terms, Material Design — make that Google — wants to use understated depth and movement to suggest what an app does and how you make it do that. And it plans to apply those ideas across devices as diverse as watches, phones, tablets, Web browsers, and TVs.

Physical but not representative

Duarte demonstrated what this would mean on a phone running an early build of the next generation of Android software. He tapped the recent-apps button — a simple square icon has replaced the current overlapping rectangles — and instead of a scrollable column of thumbnail views of open apps, I saw something that behaved more like a stack of cards. As he swiped up, the lowest card slid below the one above it.

The notifications list worked in the same way, and the artful effect looked likely to cut down on the amount of scrolling needed.

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The recent apps screen in Android’s L version. (Yahoo Tech)

Then he brought up the calculator app. Instead of hiding trigonometric functions behind an “Advanced” menu item that, in turn, hid behind a vague stack of dots, a green bar at the right could be swiped left to plug in sines, cosines, tangents, and so on. That also seemed to be an improvement.

How an Android device reacts to your touch will also change: An onscreen tap will show up as a circle appearing around where you touched, instead of the entire button illuminating.

How deep will it go?

Many of the depth effects are exceedingly subtle. “We’ve tried to make everything feel like it’s happening in the thickness of the phone itself,” Duarte said, while noting that in TV apps the perceived depth would be closer to one foot.

In contrast, Apple’s recent direction is to make individual apps feel flatter, while yet adding a sense of depth to iOS’s home screen. I asked Duarte if Material Design was meant as a response to Apple’s work, but he declined my invitation to pick it apart beyond suggesting that Apple was correct to ditch its earlier infatuation with “skeuomorphic” design that had app icons drawn like real-world objects.

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