How to integrate a map in iPhone app

I followed the this tutorial to integrate map in my iPhone app.

Here is my projectnamecontroller.m file

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad {
     NSString *url = @"http://maps.google.com/maps?q=London";
     NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:url]];
  开发者_Go百科  [webView loadRequest:request];
    [super viewDidLoad];
}

At the end the map did not show up the iPhone simulator screen. Any idea?

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If you want google map integration pls refer this previous SO question

Integrating google map in iphone app

Or you can go through MKMapView by following this tutorial