Xcode generates code with excellent whitespace...

ZAppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
  if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
      self.mainViewController = [[ZMainViewController alloc] initWithNibName:@"ZMainViewController_iPhone" bundle:nil];
  } else {
      self.mainViewController = [[ZMainViewController alloc] initWithNibName:@"ZMainViewController_iPad" bundle:nil];
  }
  self.window.rootViewController = self.mainViewController;
    [self.window makeKeyAndVisible];
    return YES;
}