[1] NSUserDefaults NSUserDefaults object used to read information and caches information in user’s default data base. Stores the data in Plist. The synchronised method of this class automatically invoked at a period of intervals to sync the memory cache the data base. ex: `[defaults synchronize];` Always returns the immutable values. Non-persistent data storage. [2] NSBundle This object locates your app in the file system from where you can access resources and use them in your programs. [3] UIResponder: Subclass of NSObject defines the interface for objects ( likely abstract class) objects responds to this class and it handles those events. It is the super class of UIApplication, UIWindow , UIView (including all of its subclasses). Handles all type of touch events, motion events. [4] NSCoder NSCoder is an abstractClass which represents a stream of data. They are used in Archiving and Unarchiving objects. NSCoder objects are...
Mobile App Developer | Technopreneur