TOMOYO Linux is a MAC (Mandatory Access Control) implementation which gives support to protect Linux systems as well as to learn, understand and analyze system behavior. Being lightweight, it results suitable for embedded systems too. This tutorial aims to show in a practical way how to make the best use of TOMOYO Linux potentials in order to study and protect embedded Linux systems, taking Android as a specific study case. Though Android is amazingly expanding its target to various kinds of devices, it was designed mainly for mobile phones. Then, unlike other embedded operating systems, it presents some peculiar characteristics which require a particular attention to apply MAC effectively. The session is directed to those who want to learn how to use TOMOYO Linux, to managers or developers interested in security concerning embedded Linux and Android, and even to anyone just wishing to take a closer glance at Android internals.