Изменить цвет заголовка панели навигации

Мое решение:

//AppDelegate.cs
public partial class AppDelegate : UIApplicationDelegate
{
    // class-level declarations
    UIWindow window;
    public static UIStoryboard Storyboard = UIStoryboard.FromName ("MainStoryboard", null);
    public static UIViewController initialViewController;

    // ...
    public override bool FinishedLaunching (UIApplication app, NSDictionary options)
    {
        window = new UIWindow (UIScreen.MainScreen.Bounds);
        initialViewController = Storyboard.InstantiateInitialViewController () as UIViewController;

        UINavigationBar.Appearance.SetTitleTextAttributes (
            new UITextAttributes () { TextColor = UIColor.FromRGB (0, 127, 14) });

        window.RootViewController = initialViewController;
        window.MakeKeyAndVisible ();
        return true;
    }
}