Application Fundamentals

How android app run in android operating system with security features:

 So every android app relies on the Linux kernel.

  1. By default, android system gives each app a unique Linux user ID which is used only by the system and is unknown to the app.
  2. Android system sets permissions for all the data in an app so that only the user ID assigned to that app can access them.
  3. Each process has its own virtual machine (VM), so an app’s program runs in isolation from other apps.
  4. By default, every app runs in its own Linux process. The Android system starts the process when any of the app’s components need to be executed.