Android Security Internals

Chapter 4. User Management

Android originally targeted personal devices such as smartphones and assumed that each device had only one user. With the increase in popularity of tablets and other shared devices, multi-user support was added in version 4.2 and extended in later versions.

In this chapter, we’ll discuss how Android manages users who share devices and data. We begin with a look at the types of users Android supports and how it stores user metadata. We then discuss how Android shares installed applications between users while isolating application data and keeping it private to each user. Finally, we cover how Android implements isolated external storage.

Multi-User Support Overview

Android’s multi-user support allows multiple users to share ...