Development of Business Application

Coad's methodology talks about development of a business application; but same is not valid if I am developing any other application.  Which approach we will adopt for rest of the cases?

It is not true that Coad's methodology talks about development of a business application rather it is a technique for derivation of the Object Model for any system. The object model describes the attributes, behavior and relations between the objects. In Object Oriented Design, each system, be it a business application or application from any other domain, is comprised of objects. These objects interact with each other to perform some functionality.

The purpose of using Coad's Methodology is only to identify those necessary objects in the systems, their relationships, their attributes, and their services in the system.