UIApplication.SharedApplication.OpenUrl(new NSUrl("MyURLScheme//"));

var asdf2 = NSBundle.MainBundle.InfoDictionary["CFBundleURLTypes"];
var asdf3 = NSBundle.MainBundle.InfoDictionary["CFBundleURLSchemes"];

var arr = (NSBundle.MainBundle.InfoDictionary["CFBundleURLTypes"] as NSMutableArray);
var urlTypes = arr.GetItem<NSDictionary>(0);
var schemes = urlTypes.ObjectForKey(new NSString("CFBundleURLSchemes")) as NSMutableArray;
var scheme = schemes.GetItem<NSString>(0).ToString();