Often we forget the end user when we develop an app. That could be fatal. We see so many good applications not usable because of poor usability and navigability. As an app creator you must know that the User Interface (UI) which helps an iPhone user experience your app must be sticky. Ease of use is a key factor that determines the success or failure of an application. The UI must be intuitive enough for average user to be able to see and use all functions and features. This is one thing which will make app users talk about the app. Ask any marketer, word of mouth publicity can impact sales exponentially which will make or break an app sales.