chosen-c.js

// by Ed
    if( /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent) ) {
        setTimeout(function(e){
            var timer = false;
            function toggle(e){
                var target = e.currentTarget;
                var $target = $(target).find('.chosen-single');
                $target.trigger('mousedown');
            }

            var start = undefined;
            $('.chosen-container').off('touchstart');
            $('.chosen-container').on('touchstart', function(e){
                start = new Date();
            });
            $('.chosen-container').on('touchend', function(e){
                if(new Date() - start < 250){
                    var t = e || event;
                    toggle(t);
                    start = undefined;
                }
            });
        }, 1500);
    }