Question

Now, when I select the annotation I reposition the view to center like this:

[mapView setCenterCoordinate:view.annotation.coordinate animated:YES];

But how can I reposition my view to center only vertically and not horizontally?

Answer 1

Make a new coordinate that has the latitude from the annotation and the current longitude

CLLocationCoordinate2D newCenter = CLLocationCoordinate2DMake(view.annotation.coordinate.latitude, mapView.centerCoordinate.longitude);

Set it as you were doing before

[mapView setCenterCoordinate:newCenter animated:YES];