In today's era as the use of smart devices takes a boom, number of mobile application developing has also get increased. With this increase it has become one of the greatest target for hackers. The flaws in the application may arise due to many reason like poor coding techniques, rush to the application release, developer's inexperience, etc. When these flaws are exploited by any hacker it could cause a great loss to the company who developed the application or the user using the application. In this session we will discuss about reversing the mobile application, hooking its methods and swizzling it.