Ipad ios 7 Comaptiblity

In my one iPad application i have to make it compatible for the ios 7 which is already exists for ios 6.0.For that i have to do below changes.

1>I have to add below two icon files for ios 7.0

-icon files 

ipad non ratina (76*76)

ipad ratina (152*152)

2> I used custom navigation bar for my app.One issue  found in ios 7.0 that statsbar is overlapped with navigation bar 

I implement this code in appDelegate

if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7) {

            [[UIApplication sharedApplication] setStatusBarStyle: UIStatusBarStyleDefault];

            for (UIView *v in self.navController.view.subviews) {

               CGRect oldFrame = v.frame;

                v.frame = CGRectMake(oldFrame.origin.x, oldFrame.origin.y + 20.0f, oldFrame.size.width, oldFrame.size.height);

            }

            [[UIApplication sharedApplication] setStatusBarStyle: UIStatusBarStyleDefault];

        }

-In all view controller to transfer all views 20 pixel down from top implement this code

 if (IS_HIGHER_IOS7) {

        for (UIView *v in self.view.subviews) {

                CGRect oldFrame = v.frame;

                v.frame = CGRectMake(oldFrame.origin.x, oldFrame.origin.y + 20.0f, oldFrame.size.width, oldFrame.size.height);

        }

    }