Comparing Flat and Edge-Screen Smartphones Operated on a One-Hand-Only Basis: A Video Observation in Laboratory Settings

This study aims to investigate the effects of edge displays on smartphone usage in one-hand-only use scenarios and identify issues related to touch errors. Experiments were conducted by recreating typical usage environments to mimic the use of phones in cafeterias, homes, and mobile settings. A framework to analyze smartphone usage and human errors was developed. We collected data on the usage errors and use cases through a head-mounted camera donned by participants and a screen-recording application. The results showed that the number of incidents involving unintentional touching of screen edges for edge-screen smartphones is five times higher than that for typical flat smartphones. Moreover, the lying down position is more susceptible to errors for both types of smartphones. These results indicate the necessity of design strategies to reduce unrelated touching of screen edges and the importance of considering various body postures to elucidate a better understanding of smartphone usage.