Practical Mobile Forensics - Fourth Edition

The iOS architecture

iOS is an intermediary between the device hardware components and the applications on the screen. The applications don't interact with the underlying hardware directly. Instead, they do it through a well-defined system interface that protects them from hardware changes. This abstraction makes it easy to build applications that work on devices with different hardware capabilities.

The iOS architecture consists of four layers: the Cocoa Touch layer, the Media layer, the Core Services layer, and the Core OS layer. Each layer consists of several frameworks that help to build an application, as illustrated in the following diagram:

The iOS layers

These layers can be described as follows:

• Cocoa Touch: This layer contains ...