This document presents a workshop on creating gymkhanas (group activities with challenges) for Android mobile devices. It discusses the general architecture of the m-Gymkhana system, which allows organizers to create challenges involving text, photos, or geolocation and monitor participant progress in real-time. The workshop will guide attendees in using the m-Gymkhana app to create and play a sample mobile gymkhana, demonstrating features like challenge types, administration tools, and real-time maps and messaging.