In this article, I will try to add as many Q&A’s related to iOS . I will keep on updating this article. Hope it helps you guys 🙂. — 1. Do we have an extension in Objective — C? The answer is YES. 2. Difference between a category and extension in objective C? A category can be declared for any class, even if you don’t have the original implementation source code. A class extension bears some similarity to a category, but it can only be added to a class for which you have the source code at compile time…