Using App Stores to Conduct Longitudinal Research

Conducting longitudinal user studies can be highly resource consuming. Thus, research groups have investigated to use emerging application distribution channels, such as Apple’s App Store or Google’s Android Market to bring the research to the user. By turning an app into an experimental apparatus we can study usage patterns that occur in-situ in real life and for a long period of time. However, these kinds of studies are still hardly understood and come along with a lot of challenges that threaten such studies’ internal validity. In this paper, we report from two case studies from our research group and elaborate the challenges we encountered.