This is delegate method of MKMapView
which call when you tap pins calloutbutton
- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control
and for annotationView (for view of pins ) use bellow delegate method..
- (MKAnnotationView *)mapView:(MKMapView *)mV viewForAnnotation:(id <MKAnnotation>)annotation