User experience and usability of physical controls(home button) on front of smartphones

Abstract

Background The front of the latest smartphones, which is beginning to be replaced by touch screens, has excluded the widely used physical controls (e.g., home buttons). Accordingly, latest smartphones, which changed suddenly appearance design disappeared home button on the front, has changed usability and user experience Disappearing physical controls affect 'trigger' and 'feedback', which are key elements of user interaction. Therefore, this research investigates the effect of the presence of a physical home button on the user experience as above. Methods Based on the released smartphones, four types of home button are classified according to physical trigger and physical feedback. Types of home button were produced as a prototype, and the participants performed the task with randomly presented prototypes after wearing eye tracking equipment. After the task was completed, the user gaze, usability, and psychology were examined by home button types through surveys and interviews. Results In the survey of user gaze, usability and psychology, the type A was the most preferred among the home button types. When the phone has a physical home button (physical trigger) and the tactile feedback (physical feedback), the user can focus more on the task and is less likely to look for the home button. On the other hand, other types of trigger and feedback that are not obvious, have been shown to be relatively negative in user gaze, usability and psychology aspects. The experience of using the latest smartphones did not show a moderating effect on user gaze and usability. However, the experience was significant in psychology. Conclusions This study shows that the type of obvious physical trigger and feedback were satisfied and less likely to confuse the user in performing tasks. Furthermore, the latest smartphones without physical controls (home button) and only a touch screen on the front can cause some confusion to users. Based on the results of this study, it is expected that follow-up studies on various physical controls and a wide range of users will be conducted.