title: Adding a welcome message once app opens
body: <p>I am trying to display a welcome message when the user launches the app. I am using the <code>UIAlertController</code> class.</p>
  
  <p>I am adding the <code>UIAlertController</code> in app delegate, here it is</p>
  
  <pre><code>- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
      // Override point for customization after application launch.
      self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
      self.window.backgroundColor = [UIColor whiteColor];
      self.window.rootViewController = [[UINavigationController alloc] initWithRootViewController:[[ViewController alloc] init]];
  
      [self.window makeKeyAndVisible];
  
      UIAlertController *alertMessage = [UIAlertController alertControllerWithTitle:NSLocalizedString(@"Welcome!", @"Welcome")
                                                                            message:@"Enjoy Using the Browser"
                                                                     preferredStyle:UIAlertControllerStyleAlert];
  
      return YES;
  }
  </code></pre>
  
  <p>I get the warning that <code>alertMessage</code> is not being used. I don't know how to go forward, any hints or tips?</p>