UILabel CreateLabel(NinjaAnnotation annotation)
 {
     var label = new UILabel(new RectangleF(-10, 27, 80, 40))
     {
         BackgroundColor = UIColor.Clear,
         TextColor = UIColor.Black,
         ShadowColor = UIColor.White,
         AdjustsFontSizeToFitWidth = true,
         Tag = LabelPinSubView,
         Font = UIFont.BoldSystemFontOfSize(14),
         Text = annotation.Title
     };
     return label;
 }
        MKAnnotationView CreatePushPin(NinjaAnnotation annotation)
        {
            const string reuseIdentifier = "NinjaPushPin";
            var view = _mapView.DequeueReusableAnnotation(reuseIdentifier) as MKPinAnnotationView;

            if (view != null)
                return view;

            view = new MKPinAnnotationView(annotation, reuseIdentifier)
                {
                    PinColor = MKPinAnnotationColor.Purple,
                    AnimatesDrop = true
                };
            view.AddSubview(CreateLabel(annotation));
            return view;
        }