The iPhone has a problem. There’s too much you can do with it.
This is a problem, you may be asking? Yes, it is, because there are so many things you can do with the device (thanks to hundreds of thousands of free or low-cost apps) that you lose track of things.
Yes, many other device makers would like to have the problem that Apple is having – millions of units sold, hundreds of thousands of apps, and a customer satisfaction rating in the 90th percentile. The problem I speak of is not a business problem, it’s a usability problem… one that I think Apple is aware of, based on the addition of spotlight search in iPhone OS 3.0 and the ability to reorganize apps from the desktop client in iTunes 9.
In the default iPhone Ui there is no hierarchy, and any structure the user creates by arranging apps on different pages is fragile (and can be broke by adding new apps from a similar “family”) – there’s no context provided. If you have more than two pages of apps, easy and ready access starts to become a thing of the past.
It’s all too much. And that leads to frustration (“where is that app?”) and a limiting user experience.
Success brings it’s own challenges, and it’s obvious that the idea of having some structure around apps is something that Apple did not think they had to deal with… until now. I fully expect that Apple will come up with some contextual visual cues (probably like how you can “label” folders with a color is OS X) that will help with this, but until then it’s a subtle problem that is causing needless frustration.
So, the lesson that this tells us? Plan for success – build into your design the appropriate information architecture that will scale as needed. And never present more options than your users are able to “handle” – that way leads to frustration (and, depending on how bad the cognitive overload is, madness and other unpleasant repercussions).