Modifying Page-Links format

One easy way to do this is to alter the global variables related to paging after calling the_post() in your loop.

global $post, $pages, $numpages, $multipage;
while( have_posts() ) {
    the_post();

    if( is_mobile() ) {
        $pages = array( $post->post_content );
        $page = $numpages = 1;
        $multipage = false;
    }

    // ... template
    the_content();
}

Basically what you’re doing is un-doing the paging setup done in setup_postdata()