Comparing Low and High-Fidelity Prototypes in Mobile Phone Evaluation

2.1. Addressing Users’ Perception of Mobile Phone Usability

To most users today, a mobile phone is not only a tool with which they can perform a task, but also a decoration and representation of their lifestyle and personality. However, in spite of how impressive the “smart” capabilities and value-added features can provide, the designers can also make the design and evaluation more complicated and the device more difficult to use. The mobile phone development professionals need to carry out careful user-centered designs with special attention to particular mobile phone characteristics that suit the user’s capability, limitation, and preference.

Therefore, the usability goals for mobile phones have been changed. Mobile phone usability is a measure of quality of use, not just indicating whether a task could be performed accurately and quickly, but also determining a difference between enjoying the process and getting frustrated. The objective measurements such as effectiveness and efficiency are not sufficient to describe the usability of a mobile phone. The feeling of the use of mobile phones is more like a subjective and personal view than an objective measure, especially from the perspective of end-users. This brings new interests and challenges to usability professionals and practitioners. They have agreed with each other that traditional usability measurements that were developed for software usability engineering are worthy of reconsideration before they are applied in mobile phones design projects (Han et al., 2000; Ji et al., 2006; Ling et al., 2007). So attempts were made to extend usability concepts to emphasize subjective aspects. Lots of research has been carried out and methodologies for evaluating the usability of mobile applications have been applied to emphasize subjective aspects and extend the concepts of usability (Han et al., 2001; Jordan, 1998). But it is still quite a challenge because there are a number of aspects of the interfaces and interactions with mobile phones that are much different from the traditional computer-based systems. It is essential to refine the measurement of usability, particularly in regard to the unique mobile-related usability issues.