PhoneGap

if you put this logic in on your "site" along wiht the cordova include, you will be able to redirect back to native html pages from a site html page.  You will have your base path for the redirect, then you just need to know the exact file name that you are trying to redirect to.
  function onDeviceReadyIOS() {
            window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, onFS, null);
        }
        function onFS(fs) {
            iOSFilePath = fs.root.toURL();
                pathForNativeRedirect = iOSFilePath.replace("/Documents", "").replace("localhost", "").replace(/ /g, '%20') + '/[your app name].app/www/';
        }
        function onDeviceReadyAndroid() {
            pathForNativeRedirect = 'file:///android_asset/www/';
        }