my .h file
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
@interface ViewerApp : UIApplication {

}

here is my .m file

#import "ViewerApp.h"
@implementation ViewerApp

-(BOOL)application:(UIApplication *)app didFinishLaunchingWithOptions:(NSDictionary *)in{
   NSLog(@"appLaunching");
    return YES;
}