[ebf]

To continue using the iPhone as an example, I realized that after two years, my Dad never realized that double clicking brings up the app switcher. I agree that it is better if you don't need a walkthrough, but I wouldn't say that you "blew it" if your app needs one. If a 30 second tutorial let's the user do very powerful and intuitive things, things that may save the user time over the long run, than maybe it is okay.

[enraged_camel]

Not really. The app switcher is not the only way to switch apps. In fact, it is the more difficult of the two. It makes you click the home button twice, then tap the app you want once - versus click the home button once, and then the app you want once. Three clicks/taps versus two. As such, it is not a huge deal at all that it is not intuitive.

Same thing with double-tap to zoom. Not terribly intuitive, but that's not a big deal because there's a "hyper-intuitive" way to zoom. Double-tap becomes necessary only in very specific situations where only the hand holding the phone is free - which is not very common.

[zevyoura]

On the other hand, the double tap brings up the four most recently used applications, which, for my usage patterns at least, are more likely to be what I'm looking for than the apps on my home screen.

[ricardobeat]

Most people put their most used apps in the home screen, so that's a tie.

[furyofantares]

I am not convinced most people organize their apps at all, or even know how to.

[mwill]

Anecdotal evidence: My father once saw me open the app switcher to force quit an app that was behaving badly. He thought it was easier, so he now checks it every single time he wants to switch an app. If it's not on the first row, he goes to the home screen and searches for it, which can take him up to a few minutes. He doesn't organise his apps in any way, and isn't interested in starting, even though he knows how to move them around.

He just likes the app switcher better.

But he never would have discovered it if not for him coincidentally paying attention when I pulled it up once.

[ebf]

Number of steps is not necessarily and indication of the speed and ease of the action. Steps != a good metric to judge a UI by. Would you really say that a double click is equivalent in cost two a single click then finding the app icon and clicking on it?

[executive]

you can also four finger swipe up to see the switcher

[dave5104]

And I just learned something new. Thanks! (But I've only had an iPhone for about a week now.)