Analysis of visual performance during the use of mobile devices while walking

Abstract

Mobile computers and smartphones are often used while their users are walking. From an ergonomic viewpoint, this requires a thorough design of the user interface. Although styleguides provide multiple recommendations there is little known about basic human factors' issues. This study provides recommendations for the visual design by analyzing the influence of walking on visual acuity with a mobile computer. N=22 volunteers participated in the experiment comparing visual acuity during standing, slow walking and fast walking. Additional conditions referred to indoor (treadmill) and outdoor (free walking) situations. The results show that walking speed has a highly significant influence on visual acuity. The results are independent of the indoor or outdoor condition. The decrease of visual acuity is similar to a row on a common eye chart. For compensating this decrease, letters and icons on a mobile device should be enlarged by about 20%. © 2014 Springer International Publishing.