Publication Date

Spring 2012

Degree Type


Degree Name

Master of Science (MS)


Industrial and Systems Engineering


Cary Feria

Subject Areas

Industrial engineering


Previous studies have examined the effects of walking and user interface elements on mobile task performance, using physical target selection tasks. The current study investigated the effect of walking and user interface elements on visual search on a mobile device, isolating the effects on perceptual and cognitive processes. The effects of object size, contrast, and target location on mobile devices while walking and standing were examined. A serial visual search using "T" and "L" shapes on a mobile device, which controlled for physical target selection involvement was conducted. The results showed that walking, bigger object size, and the target position in the outer area of the mobile device display slowed the visual search response time. This suggests that walking causes a negative performance effect not only on the physical task but also on the cognitive process while interacting with the mobile user interface. In addition, the results of the study suggest that the placing of major content and call-to-action items in the inner area of the display are likely to improve task performance on a mobile device.