Designing for Touch

A great discoverability strategy feels like a prize, not an instruction

When an interaction is important enough, it’s okay to pause and force people to try the gesture to continue.

Teach the basic interactions first, as people encounter them, before introducing more complex or abstract gestures. (Let people use those advanced gestures if they discover them on their own. Levels aren’t about holding people back from new stuff, but rather when you decide to advertise it.

The best teaching interfaces notice your activity, inactivity, and overall learning progress, and adapt their guidance accordingly.

So the designers added an animation: every time you visited the main screen, the dial zipped in from the right (FIG 5.14). “Hey, that moves, maybe I can move it too.” It worked. With the app demonstrating the motion of the control, confusion melted away and visitors swiped the dial as intended. Once you moved the dial yourself, demonstrating you’d learned the trick, the animation stopped running.

Explicit help is okay, by the way. I’ve heard designers say, “If your interface needs explanation, you’ve failed.” It isn’t true. While basic features should be easy and obvious from the get-go, advanced features always need a little instruction, even in the most well-considered interface. The best learning takes place while doing, however, which is why help screens and FAQs let us down.

Other approaches extend semantic zoom to navigate more deeply into the information hierarchy. For example, Photos for iPad offers pinch and spread as an alternate way to navigate between an album and individual photos (FIG 4.2). When you’re admiring one of your pictures, you can tap the back button to return to a thumbnail view of all the photos in the album. But you can also pinch the screen to return to that thumbnail album view. Here semantic zoom is deployed to let you move up and down the app’s organizational levels

Android adds nuance to double-tap zooming with double-tap and slide. When you slide up and down after a double-tap in Android, you can control the precise amount to zoom; sliding up zooms out and sliding down zooms in.

When we design for sensors, not just screens, the whole world becomes a digital canvas. As users, that gives us the chance to interact more directly with the people and places we truly care about, restoring some of the attention we’ve ceded to screens.

When you create an account with eBay’s app, you can skip entering your name and address by scanning your driver’s license with your camera; the app reads your info and completes the form for you.
Mobile Safari on iOS fills out payment info when you take a photo of your credit card.
Use the Google Translate app to point your camera at text in one language, and it automatically converts the text to another