MainViewController.m

// code here...

- (BOOL) webView:(UIWebView*)theWebView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType
{
    // return [super webView:theWebView shouldStartLoadWithRequest:request navigationType:navigationType];
    NSURL *url = [request URL];
    NSString *path = [url path];

    // Intercept the external http requests and forward to Safari.app
    // Otherwise forward to the PhoneGap WebView
    // if ([[url scheme] isEqualToString:@"http"] || [[url scheme] isEqualToString:@"https"]) {
    if (
        ([[url scheme] isEqualToString:@"http"] || [[url scheme] isEqualToString:@"https"]) &&
        ([[url parameterString] isEqualToString:@"external"] || [path rangeOfString:@"/external/"].location == NSNotFound)
    ) {
        [[UIApplication sharedApplication] openURL:url];
        return NO;
    }
    else {
        return [ super webView:theWebView shouldStartLoadWithRequest:request navigationType:navigationType ];
    }
}

// code here...