Chiang ZH., Wen CC., Chen AC., Hou C. (2013) An Analysis of Smartphone Size Regarding Operating Performance. In: Yamamoto S. (eds) Human Interface and the Management of Information. Information and Interaction for Health, Safety, Mobility and Complex Environments. HIMI 2013. Lecture Notes in Computer Science, vol 8017. Springer, Berlin, Heidelberg
An increasing number of electronic devices employ touchscreens as the operating method. Among these devices, smartphones have exhibited the most rapid development. To achieve more impressive visual effects, the size of smartphone displays has gradually increased. However, the resulting disadvantage is that these devices cannot be operated using one hand. In situations where users must operate the phone with one hand, some screen areas cannot be reached by their thumb. Thus, the demand for one-handed operation remains. This demand is related to operating convenience, which is obviously not provided by existing products. This study analyzes touchscreen cell phones with varying screen sizes, from 2.55 to 5.3 in, currently available on the market to examine the efficiency of one-handed operation by investigating four operating directions, that is, diagonal, horizontal, vertical, and center-cross. In addition, a customized application was developed to record the operating sequences, frequencies, numbers of errors, and positions of errors to understand the effect that display sizes have on one-handed operation. According to the analysis results, 4-in touchscreen cell phones generated the fewest operating errors, and 3-in touchscreen cell phones provided the shortest operating time. To obtain optimal visual effects, the implementation of 4-in screens for touchscreen cell phones may be the best option for one-handed operation.