calls, has a dedicated button. Checking a prepaid account balance, also very important, is available using a direct keypress. By making important functions directly available from the keypad, MotoFone enables users to more easily access the phone’s features by harnessing spatial memory.

January + February 2008

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Navigation and Spatial Memory

Nesting functions in hierarchical menus is in direct opposition to the design goal of taking advantage of spatial memory. For almost every phone, the same physical space of the screen is used to represent divergent kinds of information and functions, and there is often very little space available to provide orientation cues. In one context, the information shown on the screen might represent an address book; in another context, it is an SMS message composer or a music player. Reusing the physical space in this way runs counter to people’s natural bias toward a spatial understanding of systems.

Addressing this in the design of mobile devices is difficult: Displays are small, and the functional demands are high. Good user interfaces provide users with context about their location in a system (such as breadcrumbs in website navigation). But even in typical mobile phones, this objective is often difficult to realize. Without the luxury of large screens to provide orientation cues, mobile phones rely heavily on short, descriptive screen labels and people’s memory of where they are in the system. For those who cannot read, however, understanding these labels becomes a difficult task, as there are no spatial cues to prompt memory.

Through in-country research and concept validation, the Motorola team established a core feature set for MotoFone that was both useful and appealing to target customers. By reducing the amount of functionality available, the main navigation could, in turn, be flattened to a single-level menu that provides direct access to important functions. In this way, SMS (often necessary to check prepaid account balances), ringtone selection, alarm clock, and system clock settings are all primary functions directly available from this menu. This approach mitigates the need for users to remember where, within a complex internal hierarchy, each piece of functionality is located.

Environmental Factors

In addition to struggling with literacy, people in developing countries often have quite specific practical needs in relation to mobile phones, compared with those living in wealthier parts of the world. Through the course of the MotoFone project, the Motorola research and design team spent a great deal of time carrying out contextual research in many developing world countries. The team found that phones are very often used outside, so screens need to be highly readable in direct sunlight. Power supplies are often unreliable, so battery life becomes a critical issue. And users are very price sensitive, so tracking phone spending is an almost continuous activity.

To address these issues, MotoFone makes use of a large Electronic Paper Display, like those used in some e-books, which is exceptionally readable in full sunlight. Battery life is rated

at more than 12 days. Customized prepaid tracking features allow users to directly check their prepaid account balance with a single keypress. But perhaps most important, many design elements of MotoFone are focused on supporting people who cannot read.

Designing systems for nonliterate users creates a unique set of demands and opportunities for designers. When creating products for nonliterate people, designers should consider the following best practices:

• Harness collective literacy. Understanding the competencies of the group must be considered along with those of the individual.

• Leverage familiar images and metaphors that are culturally meaningful. Without written words, appropriate design of symbols and icons becomes critically important.

• Draw on well-developed skills, such as spatial memory. Make the most of people’s ability to remember spatial relationships.

Bringing mobile phones to the developing world can have a considerable positive impact on people’s ability to improve their lives. Designing such products in an appropriate way only enhances that opportunity.

 

ABOUT THE AUTHOR Gabriel White led the interaction design for MotoFone while working for Motorola in Beijing. Currently, he is a principal designer at frog design, a strategic-creative consultancy, based in Palo Alto, Calif. He has a keen interest in designing products for social change, and also publishes a blog dedicated to mobile interaction design at www. smallsurfaces.com.