Usability Evaluation of the Wheel Navigation Key used for Mobile Phone and MP3

The aim of the study is to investigate the usability of wheel navigation key(WNK) recently adopted for the new models of mobile phone and MP3 product. In this study, an experiment was designed to evaluate the functional benefit of WNK by using a performance test. A questionnaire was also used to examine the personal preference. In results, a significant difference was found in performance time between wheel-type and button-type product. In general, the difference was more significant as subject's skill level was higher. In particular, the performance time was significantly shortened with the WNK when a searching task was required, but push button was an effective interface for simple search task among beginners. Therefore, the wheel navigation key can be used to improve the usability of product by reducing the searching time in mobile phone and mp3. For practical application, the user's level of skill needs to be considered to maximize the effect of interface when choosing WNK or push button