Prior studies have shown benefits of interactions on mobile devices. Device mobility itself changes the nature of the user experience; interactions on mobile devices may present better support for cognition. To better understand cognitive demands related to mobility, the current study investigated presentations on a mobile device for a three-dimensional construction task. The task imposed considerable cognitive load, particularly in demands for mental rotation; individual differences in spatial ability are known to interact with these demands. This study specifically investigated mobile device orientations and participants’ spatial ability. Subjects with low spatial ability were able to complete the task more effectively when shown the presentation in a favorable orientation. Individuals who saw the presentation in an unfavorable orientation and those of low spatial ability, were differentially disadvantaged. We conclude that mobility can reduce cognitive load by limiting demands for spatial processing relating to reorientation.