In today’s mobile computing, Linux plays a significant role. The Linux kernel has been adopted by a variety of mobile operating systems to handle tasks such as device management, memory management, process management, networking, power management, application interface management, and user interface management. This chapter introduces Linux based mobile operating systems installed on various mobile devices. It first gives a brief introduction of the history of mobile Linux. Then, the chapter introduces the mobile Linux features that can be used to meet the mobile learning requirements. The last part of the chapter presents strategies on selecting a Linux based operating system for a particular mobile learning project.