Self administered surveys can be conducted over mobile web capable devices. The literature is scarce on design of mobile web surveys. Mobile web surveys have some unique functionality that will require development of new design considerations. Replication of findings from other modes as well as construction of new experiments is needed to inform design for mobile web surveys. An area probability sample from two counties in the U.S. was drawn and a household member was randomly selected and recruited by field recruiters to participate in a Smartphone panel. Ninety-two participants were provided with a Smartphone device with paid voice and data plans and asked to complete a short survey every week. A series of design experiments were launched through the weekly surveys. Experiments addressed three major objectives. First, to replicate selected findings found to be robust across modes, such as effects from question order and scale frequencies, whic are expected to work through the same cognitive processes. Second, to replicate findings from experiments in (computer administered) web surveys. Web surveys differ from other modes and share much of the functionality of mobile web surveys, both administered through web browsers. Among our experiments, we examine the use of pictures in the questionnaire and the number of questions placed on a page. Last, we devised experiments that address the unique functionality and display of the mobile device. Individuals vary in their familiarity with mobile devices that can be related to how survey design affects responding. We measured self reported familiarity with mobile devices in the initial background survey and obtained usage of voice and data services from the mobile provider, to use in multivariate models. We administered another survey a few weeks after the experiments, assigning respondents to the conditions they did not receive in the initial experiments. We conclude with practical implications, cautions, and suggestions for future research.