iOS Architecture
Architecture of iOs is a layered architecture. At the uppermost level iOS works as an intermediary between the underlying hardware and the apps you make. Apps do not communicate to the underlying hardware directly. Apps talk with the hardware through a collection of well defined system interfaces. These interfaces make it simple to write apps that work constantly on devices having various hardware abilities. Lower layers gives the basic services which all application relies on and higher level layer gives sophisticated graphics and interface related services. Apple provides most of its system interfaces in special packages called frameworks. A framework is a directory that holds a dynamic shared library that is .a files, related resources like as header files, images, and helper apps required to support that library. Every layer have a set of Framework which the developer use to construct the applications. 1. Core OS Layer: The Core OS layer holds the low lev...