Datasheet

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Chapter 1: Creating Killer iPhone Applications
This is only a partial list, of course. I get into this aspect of application design
in more detail when I take you through the design of MobileTravel411.
I suppose there are other ways to divide the tasks, but anything much dif-
ferent would be ignoring the user’s mental model — which would mean that
the application would not meet some of the user’s expectations. It would be
less pleasant to use because it would impose an unfamiliar way of looking
at things instead of building on the knowledge and experiences those users
already have.
When possible, model your application’s objects and actions on objects and
actions in the real world. For example, the iPhone has a set of iPod-style play-
back controls, tapping controls to make things happen, sliding on-off switches,
and flicking through the data shown on Picker wheels. All of these are based
on physical counterparts in the real world.
Your application’s text should be based on the target user. For example, if
your user isn’t steeped in technical jargon, avoid it in the user interface.
This doesn’t mean that you have to “dumb down” the application. Here are
some guidelines:
✓ If your application is targeted for a set of users who already use (and
expect) a certain kind of specialized language, then sure, you can use
the jargon in your application. Just do your homework first and make
sure that you use those terms correctly.
For example, if your application is targeted at high-powered foreign-
exchange traders, your application might use pip (“price interest point” —
the smallest amount that a price can move, as when a stock price
advances by one cent). In fact, a foreign-exchange trader expects to see
price movement in pips, and not only can you, but you should use that
term in your user interface.
✓ If your application requires that the user have a certain amount of spe-
cialized knowledge about a task in order to use the application, identify
what that knowledge is upfront.
✓ If the user is an ordinary person with generalized knowledge, use ordi-
nary language.
Gear your application to your user’s knowledge base. In effect, meet
your users where they are; don’t expect them to come to you.
Disappearing the Technology
Although a few people out there actually love the gadgetry associated with
mobile (or any) technology, at the end of the day, when you want to get
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