vwMapis the name of the object MKMapview:
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(foundTap:)];
tapRecognizer.numberOfTapsRequired = 1;
tapRecognizer.numberOfTouchesRequired = 1;
[vwMap addGestureRecognizer:tapRecognizer];
-(IBAction)foundTap:(UITapGestureRecognizer *)recognizer {
CGPoint point = [recognizer locationInView:vwMap];
CLLocationCoordinate2D tapPoint = [vwMap convertPoint:point toCoordinateFromView:vwMap];
MKPointAnnotation *point1 = [[MKPointAnnotation alloc] init];
point1.coordinate = tapPoint;
[vwMap addAnnotation:point1];
}