The system architecture of iOS is divided into four levels: the core OS layer, the core service layer, the media layer, and the Cocoa Touch layer. System operation takes up approximately 240MB of memory space.
The iOS interface iOS user interface concept is based on the ability to use multi-touch direct operation. Control methods include sliding, tactile switches and buttons. Interaction with the system includes swiping, tapping (ta ppi ng), pinching, and reverse pinching. In addition, with its built-in accelerator, its rotating device can change its y-axis to change the direction of the screen. This design makes the iPhone more convenient to use. There is a home button at the bottom of the screen, and a dock at the bottom. The icons of the programs most frequently used by four users are fixed on the dock.
On the iPhone, many applications are connected so that different applications can share the same information (for example, when you receive a short message that includes a phone number, you can choose to save the phone number) For the contact person or directly select this number to make a call).
The iPhone and iPod Touch use an ARM-based CPU instead of the x86 processor used by Apple's Macintosh computers (like the previous PowerPC or [MC68000|MC680x0]), which uses rendering by PowerVR video cards. OpenGL ES 1.1.
Therefore, applications on Mac OS X cannot be copied directly to iOS to run. They need to be rewritten for ARM for iOS. Starting with iOS 2.0, third-party apps that have been reviewed have been published and downloaded through Apple's App Store.