Slider Page Display Problem on Mobile Devices

I’ve paid for a workaround to stop the slider displaying on mobile devices, but I would really like to address the problem.

Please, could someone suggest why the slider causes display problems on mobile devices?

I haven’t found a solution to this. Any suggestions – Please?

I’m wondering if the code I copied and pasted it into functions.php to make the slider progress automatically might be causing the problem. It works… but now I’m thinking it’s missing a ?> tag after the last </script>. Am I right? As I’ve broken my site before by making mistakes in functions.php, and I don’t have direct access to the server files, I’m nervous to make changes. I’d be very grateful if someone would have a look at the following code and advise:

<?php
if ( ! isset( $content_width ) ) {
	$content_width = 474;
}
/**
 *DD MAKE FEATURED IMAGES SLIDE
 */
function add_script_in_footer(){
?>
<script type="text/javascript" charset="utf-8">
    jQuery(document).ready(function(){
        var change_every = 3; // The number of seconds that the slider will auto-advance in
        var current = 1;
        function auto_advance(){
            if(current == -1) return false;
            jQuery('#featured-content .slider-next').eq(current % jQuery('#featured-content .slider-next').length).trigger('click', [true]);
            current++;
        };
        setInterval(function(){auto_advance()}, change_every * 1000);
    });
</script>

<?php