@property (strong, nonatomic) UINavigationController *navController;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    frstVwCntlr = [[firstViewController alloc] initWithNibName:@"firstViewController" bundle:nil];
    self.navController = [[UINavigationController alloc] initWithRootViewController:self.frstVwCntlr];
    self.window.rootViewController = self.navController;
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    self.window.backgroundColor=[UIColor clearColor];

    self.viewController = [[YourFirstViewController alloc] initWithNibName:@"YourFirstViewController" bundle:nil];
    UINavigationController *navController=[[UINavigationController alloc]initWithRootViewController:self.viewController];
    self.window.rootViewController = navController;
    [self.window makeKeyAndVisible];

    // Override point for customization after application launch.
    return YES;
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{

self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.window.backgroundColor=[UIColor clearColor];

self.viewController = [[YourViewControllername alloc] initWithNibName:@"YourViewControllername" bundle:nil];
UINavigationController *navController=[[UINavigationController alloc]initWithRootViewController:self.viewController];
self.window.rootViewController = navController;
[self.window makeKeyAndVisible];

// Override point for customization after application launch.
return YES;
}

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
ImageViewController2 *dealVC = (ImageViewController2 *)[storyboard instantiateViewControllerWithIdentifier:@"ImageViewController2"];
[self.navigationController pushViewController:dealVC animated:YES];