Usability - iPad UI's suffering birth pains

Post date: May 17, 2010 3:32:40 AM

I love iPad, its so sexy (I fawn over it in a blog entry iPad droolage) but............

iPad apps are inconsistent and have low feature discoverability, with frequent user errors due to accidental gestures. An overly strong print metaphor and weird interaction styles cause further usability problems.......

iPad UIs suffer under a triple threat that causes significant user confusion

• Low discoverability: The UI is mostly hidden within the etched-glass aesthetic without perceived affordances.

• Low memorability: Gestures are inherently ephemeral and difficult to learn when they're not employed consistently across apps; wider reliance on generic commands would help.

• Accidental activation: This occurs when users touch things by mistake or make a gesture that unexpectedly initiates a feature.

"It looks like a giant iPhone," is the first thing users say when asked to test an iPad. (Their second comment? "Wow, it's heavy.")

But from an interaction design perspective, an iPad user interface shouldn't be a scaled-up iPhone UI.

Indeed, one finding from our study is that the tab bar at the bottom of the screen works much worse on iPad than on iPhone. On the small phone, users are likely to notice the muted icons at the bottom of the screen, even if their attention is on content in the middle of the screen. But the iPad's much bigger screen means that users are typically directing their gaze far from the tab bar and they ignore (and forget) those buttons.

Another big difference between iPad and iPhone is that regular websites work reasonably well on the big tablet. In our iPhone usability studies, users strongly prefer using apps to going on the Web. It's simply too painful to use most websites on the small screen. (Mobile-optimized sites alleviate this issue, but even they usually have worse usability than apps.)

The iPad's bigger screen offers reasonable usability for regular Web pages. Of course, there's still the "fat finger" problem common to all touch screens, which makes it hard for users to reliably hit small targets. The iPad has a read–tap asymmetry, where text big enough to read is too small to touch. Thus, we definitely recommend large touch zones on any Web page hoping to attract many iPad users.

When you combine these three usability problems, the resulting user experience is frequently one of not knowing what happened or how to replicate a certain action to achieve the same result again. Worse yet, people don't know how to revert to the previous state because there's no consistent undo feature to provide an escape hatch like the Web's Back button.

So his testing of the iPad makes you know that all that gorgeous new technology is just that....new. The iPad will settle out and become the wondrous usable enhancement that we all know it will be soon...but for those of us that look at Apple and usually just stare in dumbfounded amazement at their awesomeness...this helps remind us that they develop stuff the same way you or I do.