Changes

The majority of coding that is involved in developing applications for the iPad consists of interacting with and responding to the device hardware in a variety of ways. Given this fact it is worth taking some time to look at the underlying hardware contains contained in the shell of an iPad. The focus of this overview will be the iPad 2 since this is the currently shipping device at the time of writing.

Before we delve into the hardware of the iPad we will start by talking about the operating system that sits on top of all the hardware. This operating system is called iOS 4 and is a variant of Apple’s Mac OS X operating system that was originally adapted to run on the iPhone and then subsequently used on the iPad. It is built upon a “UNIX-like” foundation called Darwin and consists of the Mach kernel, core services and media layers and the Cocoa Touch interface. iOS 4 is covered in greater detail in the chapter entitled iOS 4 Architecture and SDK Frameworks.