b.Application Controller
This pattern puts foundation stone of MVC and is of academic interest only
Motivation
To control UI transtition logic in a central place.
Summary
Centralize the flow of the application and screen navigation, so that you can change flow or logic in a single location, with no changes (or minimal changes) to the source code of views.
Minimize the effort required to update the page flow logic.
Minimize page flow logic code duplication in views.
When to Use
Obsolete Pattern
Related Patterns
Model View Presenter : This pattern can be used with MVP to achieve MVC like goal.
References