Launch the compass app from within iPhone app

I'm trying something like this to launch the compass from within my app:

    NSString *stringURL = @"comp开发者_如何学JAVAass://";
    NSURL *url = [NSURL URLWithString:stringURL];
    [[UIApplication sharedApplication] openURL:url];

does anyone know the correct url to use to launch the compass app?

http://wiki.akosma.com/IPhone_URL_Schemes - I'm using this as a reference, but nothing about the compass is posted.

thanks for any help.

A quick look at Compas.app's Info.plist shows no declaration of custom URL type, which means there is no public way to open it from your app, sorry.

The compas app does not have an app URL.

does anyone know the correct url to use to launch the compass app?

What makes you think there is one?

I do not believe the compass app registers any URL scheme. This is completely optional from the developers point of view and is not implemented for all applications.