Every iOS application has its own application sandbox. An application sandbox is a directory on the filesystem that is barricaded from the rest of the filesystem. Your application must stay in its sandbox, and no other application can access your sandbox.
Figure 14.2 Application sandbox
The application sandbox contains a number of directories:
This directory contains all the resources and the executable. It is read-only.
This directory is where any preferences are stored and where the Settings application looks for application preferences. Library/Preferences is handled automatically by ...