The iPhone is Not Easy to Use: A New Direction for User Experience Design

Even worse are the modal gestures such as shake to undo and swipe to delete. If users discover them at all it’s usually by accident. They don’t map to anything (outside of an Etch-a-Sketch) and there are no clues to indicate that they’re available. Being mentioned in a WWDC keynote does not count as a clue.

I have a lot of experience critiquing user interfaces, especially from a Norman-esque viewpoint, and would like to point out that while the above criticisms have some merit, they are practically negated by the fact that nearly every iPhone commercial puts these gestures front and center. Because the ads effectively serve as tutorials, people who've never owned or used an iPhone can nevertheless walk into an Apple store knowing how to use it. You can even just walk into a store and watch one of the videos they have running--one hardly has to consult a WWDC keynote, for crying out loud.

It is also vastly easier to show a computer illiterate person how to zoom, undo, etc. using these gestures than it is to do the same on a desktop. You can't get much better than this, frankly. That there is a literacy requirement at all is not evidence of bad design: you still have to learn how to hold a pencil, after all. It's astounding that Apple's managed to reduce the literacy requirements as much as they have.

http://www.useit.com/alertbox/981115.html

Note that 3D works for games because the user does not want to accomplish any goals beyond being entertained. It would be trivial to design a better interface than DOOM if the goal was to kill the bad guys as quickly as possible: give me a 2D map of the area with icons for enemy troops and let me drop bombs on them by clicking the icons. Presto: game over in a few seconds and the good guys win every time. That's the design you want if you are the Pentagon, but it makes for a boring game.

The guy does undersell the iPhone's usability, though. In particular, the key phone feature -- dialing the name of someone on your contact list -- is far more usable than an old-school dial telephone (where you have to remember a number) and likewise far more usable than on a cheap cell phone (where you have to do a lot of button-press scrolling, or use a numeric keypad to type the letters of someone's name... which means you have to remember the name in advance.) Indeed, the iPhone has exactly what the usability folks have been agitating for for years: A big flat list of people's names or pictures, where you touch one and it immediately dials them.

I think the moral of that story is Pareto's Rule: if you nail the usability of one common feature, people will praise your device's usability in general, even if the rest of it plays out like an adventure game.

Now that those features have been added and the UI for the iPhone has become more distinct from the Mac, you get the critique that it is all way too complex.

It's ridiculous to pick on the iPhone for its "swipe" and "shake" gestures, declare it "hard to use", and look for some other adjective that doesn't have to do with usability to explain its strengths.

Heaven forfend!

Also, the other glaring example here is the one about the mail client refresh-vs-reply arrows. Aren't these two icons the exact same icons used for pretty much the whole history of the internet? Circular arrows = refresh; Left arrow = reply.

New things sometimes require just a bit of effort because you aren't familiar with it. In other words, easy-to-use != just like every other phone out there. It's pretty close to a 'fundamentally new UI' - just because you don't grok it within 5 seconds doesn't make it hard to use.