Muhammad Imad Qureshi wrote:For example back button.
Overriding Back button may or may not be always required. It depends.
Ankit Garg wrote:I don't think there are any universal rules as to which events you should handle. It depends a lot upon the nature of the application you are creating...
Would second Ankit here.
However, there are certain "cases" that your code must be able to handle or tolerate(like screen orientation, low battery, incoming phone call etc.)