title: How to change source code in aosp and add our own application on it
body: <p>I have just downloaded Froyo source code to modify that but i don't understand where to start. I want to know the location of several system apps, including Settings in android source code. I want to add my own working Android app in Froyo source so it will start as system app. How should I proceed? Thanks in advance. </p>
  
  <p>If you have ever downloaded Froyo source code, please share the folder structure.</p>