TechStep is a randomized trial of a mobile health intervention targeted towards transgender adolescents. The interventions include an automated short messaging system, a mobile-optimized web application with social networking components, and personalized electronic counseling. The outcomes are PrEP uptake/adherence and self-reported sexual risk behaviors. The trial will be sequentially randomized in order to evaluate the efficacy of several different combinations of mHealth interventions. In this talk, I will discuss the motivation for this design, the complications in planning and analysis induced by the design, and some methods for providing robust analysis of the trial data.