Many libraries have developed mobile versions of their websites. In order to understand their users, web developers have conducted both usability tests and focus groups, yet analytical software and web server logs can also be used to better understand users. Using data collected from these tools, the Ursula C. Schwerin Library has made informed decisions regarding the development of its web-based library services for its mobile users. As a result, it has deployed a Drupal-based plug-in to support such visitors to its website. (Contains 4 figures.)