title: iPhone - remove pin annotations of map, but not mine
body: <p>I use a MapView and I set annotations on it (purple pins) and my user location (which is a blue circle).
  Because the purple pin annotations will move, I have to remove and set them new to the map.</p>
  
  <p>I set it with:</p>
  
  <pre><code>CLLocationCoordinate2D coordinate;
  coordinate.latitude = 49.2802;
  coordinate.longitude = -123.1182;
  NSUInteger count = 1;
  for(int i = 0; i &lt; 10; i++) {
      CGFloat latDelta = rand()*.035/RAND_MAX - .02;
      CGFloat longDelta = rand()*.03/RAND_MAX - .015;
      CLLocationCoordinate2D newCoord = {coordinate.latitude+latDelta, coordinate.longitude+longDelta};
      MyMapAnnotation* annotation = [[MyMapAnnotation alloc] initWithCoordinate:newCoord andID:count++];
      [mapView addAnnotation:annotation];
      [annotation release];
  }
  </code></pre>
  
  <p>Before that, I do a</p>
  
  <pre><code>[mapView removeAnnotations:mapView.annotations];
  </code></pre>
  
  <p>but this line also remove my location with the blue point!
  How could I do this without removing my location.</p>
  
  <p>Thanks a lot in advance &amp; Best Regards.</p>