iOS has a layered architecture. The four layers that make up the iOS Architecture each provide a programming foundation for building applications that run on top of the hardware.
The layers between the Application Layer and the Hardware Layer will improve communication.
A lower-level layer provides all applications' necessary services.
In contrast, graphics and user interface services are provided by an upper-level layer (also known as a high-level layer).
The iPhone OS stack's bottom layer, the Core OS (or Application) Layer, rests directly on top of the device's hardware.
This layer offers low-level networking, access to external accessories, and other functions in addition to the essential operating system services, including memory management, processing of file systems and threads, and memory management.
The service layer's job is to design the services that users or layers above need. Other essential features include iCloud storage, Grand Central Dispatch, in-app purchases, and block objects. The addition of ARC Automatic Reference Counting has enhanced the service layer.
It manages media types like graphics, audio, and video. Thanks to the media layer, we can utilize the entire system's audio, video, and graphic capabilities.
The application layer is another name for the Cocoa Touch Layer. When applications are built, this is where frameworks are made. Additionally, it serves as the operating system's user interface for iOS users. This includes the ability to touch and move.