Display Footer Shortcode Different for Logged In Users

You can use a conditional tag to check if the user is logged in. Conditionals are very common in W, I would suggest you give this page a read.

Here is an example.

function footer_shortcode(){
    if (is_user_logged_in()){
        echo '
            // Logged In Content
        ';
    }else{
        echo '
            // Logged Out Content
        ';
    }       
}

add_shortcode('footerShortcode', 'footer_shortcode');