title: subviews and performance issues in iOS
body: <p>I have different view controllers and i linked them using insertsubview <br>
  There are atleast three levels of subviews for every screen the users sees.<br>
  I havent tested it on device yet.<br>
  I want to know whether this causes any performance issues<br>
  Also, is using NavigationBarController pop and push views better than addsubview and remove from super view. <br>
  (I dont want the back functionality of NavigationBarController and want a custom header. That is why i didnt use NavigationBarController)</p>