Nirvana: The Sweet Spot

When designing applications for handhelds, you must carefully determine which features to add and which ones to leave out. Recall from the earlier discussion about the essence of handhelds that including too many features in a handheld product degrades the user experience. For instance, too many features in an application can clutter the relatively small screen with lots of buttons and icons and such.

Balance features with the user experience

Your product needs enough features for the optimal user experience and no more. You may even have to omit some interesting features for the sake of a better overall user experience. The sweet spot at which you achieve an optimal balance of features and user experience appears at the apex of the curve in a graph of features vs. user experience, as shown in

Figure 1.4 Different views on new features

Determining an optimal set of features is like finding diamonds in a mountain. You don't want the whole mountain, just the important chunks.

The graph in Figure 1.4 also provides a reminder of the difference between PC thinking and handheld thinking. PC thinkers look only at the features axis. They neglect the question of whether the user benefits from these features and whether new features make the product too complicated to use.

Handheld thinkers look at the overall curve. They see that piling on features in the style of in the PC style would move Palm OS products lower on the user-experience axis. When PC thinkers recommend rushing along the features axis to make a product seem better, handheld thinkers know this could make the product worse.

In the early days, critics said to Palm: "You guys are idiots for not matching PC features. Customers want more features no matter what. And they're going to decide to buy based on a check list of features." Palm product designers did their testing, held their ground, and brought out a product that people—ordinary people—could use from the first day and every day thereafter.

This conviction and leap of faith paid off. The Palm OS platform now commands 80% of the handheld market. PalmSource licensees market a host of useful and popular products based on these underlying principles.

Added features must improve the user experience

Handheld thinking is about balancing available technology and utility. When faced with the possibility of a new feature, ask two questions:

• What do we gain in user satisfaction?

• What does it cost in terms of user confusion and hardware resources?

Let's consider an example. A proposal to add a menu bar that's always visible should be vetoed reflexively, because the handheld screen is too small. But how about displaying the menu bar whenever the user taps the application's title tab? This improvement, part of the Palm OS since version 3.5, has no negative effect on the novice user, but adds flexibility for the power user. It also costs nothing in hardware resources.