.h file

    #import <MapKit/MapKit.h>

    #define METERS_PER_MILE 1609.344

    @interface mymapViewController : UIViewController <MKMapViewDelegate,MKAnnotation,CLLocationManagerDelegate> {

        CLLocationManager *locationManager;
        IBOutlet MKMapView *map;
    }


.m file

- (void)viewDidLoad {
    [super viewDidLoad];

        //CLLocationCoordinate2D zoomLocation;
    //    zoomLocation.latitude = 23.0000;
    //    zoomLocation.longitude = 72.4000;
    //    // 2
    //    MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(zoomLocation, 500000, 500000);
    //    // 3
    //    MKCoordinateRegion adjustedRegion = [map regionThatFits:viewRegion];                
    //    // 4
    //    [map setRegion:adjustedRegion animated:YES];

        map.showsUserLocation = YES;

        locationManager = [[CLLocationManager alloc] init];
        locationManager.delegate = self;
        locationManager.distanceFilter = kCLDistanceFilterNone; 
        locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;
        [locationManager startUpdatingLocation];

        //float a = 23.000;
    //  float b = 73.000;

        NSMutableArray * arr = [[NSMutableArray alloc]init];
        [arr addObject:@"23.000"];
        [arr addObject:@"73.000"];
        [arr addObject:@"73.000"];
        [arr addObject:@"23.000"];

        CLLocationCoordinate2D coordinate;
        coordinate.latitude = locationManager.location.coordinate.latitude;
        coordinate.longitude = locationManager.location.coordinate.longitude;      
        MyLocation *annotation = [[[MyLocation alloc] initWithName:@"current" address:@"sas" coordinate:coordinate] autorelease];
        [map addAnnotation:annotation]; 

        for (int i = 0 ; i < 2; i++) {
            CLLocationCoordinate2D coordinate1;
            coordinate1.latitude = [[arr objectAtIndex:i] floatValue];
            coordinate1.longitude = [[arr objectAtIndex:i+1] floatValue];
            MyLocation *annotation1 = [[[MyLocation alloc] initWithName:@"hello" address:@"sas1" coordinate:coordinate1] autorelease];
            [map addAnnotation:annotation1];
        }




        MKCoordinateRegion region;
        MKCoordinateSpan span;
        span.latitudeDelta=1.1;
        span.longitudeDelta=1.1;
        region.span=span;
        region.center=CLLocationCoordinate2DMake(coordinate.latitude, coordinate.longitude);
        [map setRegion:region animated:TRUE];

    }


    - (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
    {
        static NSString *identifier = @"MyLocation";   
        if ([annotation isKindOfClass:[MyLocation class]]) {
            MyLocation *location = (MyLocation *) annotation;

            MKPinAnnotationView *annotationView = (MKPinAnnotationView *) [map dequeueReusableAnnotationViewWithIdentifier:identifier];
            if (annotationView == nil) {
                annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
            } else {
                annotationView.annotation = annotation;
        }

        annotationView.enabled = YES;
        annotationView.canShowCallout = YES;



            //if ([location.name compare:@"hello"] == NSOrderedSame) {
    //            annotationView.pinColor = MKPinAnnotationColorGreen;
    //      }else {
    //          annotationView.pinColor = MKPinAnnotationColorPurple;
    //      }

            return annotationView;
        }
        return nil;
    }

                Mylocation.h

                    #import <MapKit/MapKit.h>

                    @interface MyLocation : NSObject <MKAnnotation> {
                        NSString *_name;
                        NSString *_address;
                        CLLocationCoordinate2D _coordinate;
                    }

                    @property (copy) NSString *name;
                    @property (copy) NSString *address;
                    @property (nonatomic, readonly) CLLocationCoordinate2D coordinate;

                    - (id)initWithName:(NSString*)name address:(NSString*)address coordinate:(CLLocationCoordinate2D)coordinate;

            Mylocation.m


            @synthesize name = _name;
            @synthesize address = _address;
            @synthesize coordinate = _coordinate;

            - (id)initWithName:(NSString*)name address:(NSString*)address coordinate:(CLLocationCoordinate2D)coordinate {
            if ((self = [super init])) {
                _name = [name copy];
                _address = [address copy];
                    _coordinate = coordinate;
                }
                return self;
            }

        - (NSString *)title {
            return _name;
        }

        - (NSString *)subtitle {
            return _address;
        }

        - (void)dealloc

    {
        [_name release];
        _name = nil;
        [_address release];
        _address = nil;    
        [super dealloc];
    }

    @end