We reflect on the evolution of an instrument designed to gather data about student actions with dynamic textbooks in university mathematics in a large-scale project. We also discuss the evolution of our understanding of the mediating role of this instrument in gathering data remotely that allow us to access student use and reconstruct their actions. We describe how the context generated opportunities and challenges to obtain information about student textbook use. The evolving process of data collection provided insights into the relationship between researchers, participants, context, and data collection systems, and the ways in which these inform each other.