Changes

These operating system layers can be presented diagrammatically as illustrated in the following figure:

[[Image:iphone_os_architecture.png|A diagram illustrating the architecture of the iPhone OS]]

Some diagrams designed to graphically depict the software stack of the iPhone OS show an additional box positioned above the Cocoa Touch layer to indicate the applications running on the device. In the above diagram we have not done so since this would suggest that the only interface available to the app is Cocoa Touch. In practice, an app can directly call any of the layers of the stack to perform tasks on the device.