As mobile Internet access has proliferated throughout much of the United States, people invited to participate in Web-based surveys are using their mobile devices (smart phones, tablet computers, etc.) to participate in those surveys. Unfortunately, our understanding of the response process, particularly the role of memory and cognition, and our understanding of the usability challenges of small displays lead us to believe that responses entered using the small screens and keyboards of mobile devices may be of lower quality that those entered on devices with larger screens, especially for surveys that are not optimized for smaller screens. This paper uses responses to the 2011 National Survey of Student Engagement (NSSE) to explore this potential problem. Web browser data were captured from nearly 415,000 of the undergraduate college students who participated in the 2011 NSSE administration. This paper explores the demographic characteristics and response quality of the over 17,000 – 4.1% – respondents who exclusively used a mobile device to participate in the Web-based version of this survey, an instrument not optimized for mobile devices. First, demographic characteristics of these respondents are described using descriptive statistics, tests of significance, and logistic regression. Second, the quality of their responses is explored by comparing their responses to other sources of data, examining item non-response, and calculating an indicator of satisficing (Chen, 2011). The results – mobile device users tended to be older, male, and non-White and their responses were of lower quality – can inform future survey design and administration processes. In particular, these results can help us determine if the cost of optimizing for small screens is worth paying or if the potential lessening of response quality is acceptable.