Enlarging Usability for Ubiquitous Displays

As we consider ubiquitous systems that display information on large screen interfaces, we must find reasonable methods for obtaining usability assessments. Standardized, generic methods provide appeal since they allow ready application, benchmarking, and comparison of results. However, critical usability concerns for these interfaces may demand more focused evaluation methods with interface-specific evaluation tools. This work probes at the tradeoffs for usability evaluation of ubiquitous systems— particularly between using specific and generic survey tools to support a claims analysis process. Our study involves formative user interface testing of two ubiquitous large screen display notification systems, each with a generic and specific survey tool. We analyze survey tool performance in supporting immediate and long-term design needs, demonstrating the relative utility of each tool. The evidence we present clarifies the tradeoff between using specific and generic usability evaluation tools—favoring the generic tools—an important finding as tool development efforts proceed for usability evaluation of ubiquitous systems.