Personal digital assistants (PDAs) are perhaps the most interesting class of products currently being developed because of the dynamic nature of the market and the high degree of experimentation currently underway in PDA design. The PDA concept combines the potential for high functionality and an information-rich display size, with a much smaller form-factor than a notebook computer. As more functions are integrated into the PDA, it may displace the notebook computer as the platform of choice for consumer access to general purpose portable computing.

To understand the evolution of the PDA and portable electronics in general, it is instructive to look at the history of this product concept and the design of some early PDA products.

The concept for PDA products evolved from electronic organizer products developed by Japanese manufacturers in the 1980s. Electronic organizer products of this era, such as the Casio Boss and Sharp Wizard, were essentially beefed-up calculator products that enabled the user to store contact information, calendar appointments, and memos. Around 1987, Casio came up with the Casio IF-8000 (Fig. 10.1 Casio IF-8000). This product incorporated a touch sensitive display that allowed the user to input and store notes in the form of digitized pen input.

Figure 10.1: Casio IF-8000.

In 1991, Kyocera developed a very novel product called the Kyocera Refalo (Fig. 10.2). The Refalo product was constructed to resemble a ring binder style paper-based organizer. In fact, the product was designed to combine both traditional paper-based personal organization with digital technology. The left...