Mobile computing technology at Vindigo

Abstract

Developing widely useful mobile computing applications presents difficult challenges. On one hand, mobile users demand intuitive user interfaces, fast response times, and deep relevant content. On the other hand, mobile devices have limited processing, storage, power, display, and communication resources. Vindigo has taken a technology-intensive approach to meeting these challenges and has created personal navigation tools that many people find useful in their everyday lives. Vindigo's Palm OS application, introduced in March 2000, has hundreds of thousands of users and continues to attract new users rapidly.This article presents some of the technology behind Vindigo. To provide context, it first gives an overview of a typical user session. It then discusses special demands and constraints placed on mobile applications, and enumerates design principles drawn from these considerations. The rest of the article describes technology developed at Vindigo according to those principles. Throughout, it emphasizes techniques that have proven effective in delivering location-based services on today's handheld devices. User interfaceAt the time of this writing, Vindigo offers electronic guides to 20 major cities, including New York, San Francisco, and London. The guides provide information in three broad areas: dining, shopping, and entertainment. Content comes from established publishers such as The New York Times, The San Francisco Chronicle, and Zagat Survey. Vindigo's namesake guide application is available for Palm OS devices and WAP phones; a Pocket PC version is under development. Because of space considerations, the following discussion concentrates on the Palm OS version of Vindigo.A user session begins with the home screen, shown in Figure 1.a. This screen provides access to the three main content areas (eat, shop, and play) and to a facility for wirelessly sending a copy of the application to another device (give). It also allows switching between cities.A typical session continues with the user specifying a geographic location. Figure 1.b shows an example of the location selector screen. The user chooses a street intersection by scrolling through two lists of street names. The lists can be narrowed by neighborhood. In addition, once a street in one list has been selected, the other list shows only intersecting streets. Defaults further speed up selection. For example, a neighborhood's central intersection is automatically selected when the neighborhood is first specified. Searching streets by name is also possible, in which case lists display only names matching a given search prefix. Finally, the application maintains lists of recently chosen and favorite locations for later use.Vindigo also supports automatic location, for example by obtaining the current latitude and longitude from one of several GPS receivers available for Palm OS devices. These coordinates are translated into the nearest street intersection, and the session continues as before. Automatic location is convenient in many situations, but there ...

Designing a usable mobile application for field data collection

“…The second case study focuses on a handheld (PDA and WAP phone) tour guide system from Vindigo (Caceres R. et al, 2002). The software provides tour information in areas of dining, shopping and entertainment based on contextual information such as time of day, personal preferences and most importantly, the geographical location of the user.…”