The primary reason that modern architectural patterns have moved away from MVC is that the Controller in MVC generally embodies too much application code and becomes unwieldy, thereby being difficult to test. This has led to patterns that not only replace the Controller with something else, but that add multiple layers in its place to further establish a separation of concerns within an application.
In the world of iOS, Apple's mobile operating system, MVC was long encouraged as the pattern to follow. More recently, however, many iOS developers have moved away from pure MVC and have adopted patterns that establish more than just three layers within an application's architecture. One of these patterns is VIPER, which stands for View, Interactor, Presenter, Entity, and Routing (or Router).
Let's briefly cover what each of these components is:
View: Just as with MVC, the View represents the user interface.
Interactor: Contains the business logic for a particular...