Tribalpixel

or you can simply disable fancybox in your theme directly:
and dont’t care of the option in option page 😉

by using something like that:

if( wp_is_mobile() ) {
  wp_enqueue_script('ngg-photoswipe-disable-fancybox.js',get_template_directory_uri().'/js/ngg-photoswipe-disable-fancybox.js', array( 'jquery' );
}

n.b.
copy ngg-photoswipe-disable-fancybox.js from plugin directory in your theme directory

solution:
in ngg-photoswipe.php, put the update_option in the if ($_REQUEST[‘nggphotoswipe_enabled’]) on line 73

if ($_REQUEST['nggphotoswipe_enabled']) {
  update_option('nggphotoswipe_enabled',$_REQUEST['nggphotoswipe_enabled']		;
  update_option('additional_viewers',$_REQUEST['additional_viewers']);
}

i suggest somthing like: jQuery Hotkeys Plugin 🙂
https://github.com/jeresig/jquery.hotkeys