ios6以下我们一般用google地图来导航，但ios6中调用会有点问题，会打开web浏览器再询问之类的，不直观友好。所以在ios6中建议直接用apple map。本来调用apple map应该和调用google map类似，但使用：

http://maps.apple.com/maps?saddr=%f,%f&daddr=%f,%f 会提示无法定位，不知道为什么？

使用maps://saddr=%f,%f&daddr=%f,%f 会找不到当前位置，也不清楚原因？

不过还是找到了解决方法，如下（包括两种地图调用方式）：

if (SYSTEM_VERSION_LESS_THAN(@"6.0")) { // ios6以下，调用google map

            NSString *urlString = [[NSString alloc]

                        initWithFormat:@"http://maps.google.com/maps?saddr=%f,%f&daddr=%f,%f&dirfl=d",

                        cutLat,cutLon,stationLat,stationLon];

            NSURL *aURL = [NSURL URLWithString:urlString];

            [urlString release];

            [[UIApplication sharedApplication] openURL:aURL];

        } else { // 直接调用ios自己带的apple map

            CLLocationCoordinate2D to;

            to.latitude = stationLat;

            to.longitude = stationLon;

            MKMapItem *currentLocation = [MKMapItem mapItemForCurrentLocation];

            MKMapItem *toLocation = [[MKMapItem alloc] initWithPlacemark:[[[MKPlacemark alloc] initWithCoordinate:to addressDictionary:nil] autorelease]];

            toLocation.name = @"Destination";

            [MKMapItem openMapsWithItems:[NSArray arrayWithObjects:currentLocation, toLocation, nil]

                           launchOptions:[NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:MKLaunchOptionsDirectionsModeDriving, [NSNumber numberWithBool:YES], nil]

                                                                     forKeys:[NSArray arrayWithObjects:MKLaunchOptionsDirectionsModeKey, MKLaunchOptionsShowsTrafficKey, nil]]];

            [toLocation release];

        }

记得加上：

#define SYSTEM_VERSION_LESS_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)