Yake on "Disable random post function on mobilesite"

Hello!

I have a function that makes the order of my posts appear random.

It looks like this

session_start();

add_filter( 'posts_orderby', 'randomise_with_pagination' );
function randomise_with_pagination( $orderby ) {

I would like to disable this function on the mobile site. But im not sure how to do this, do you guys have any tips?

Regards
Jakob