diff --git a/tail.php b/tail.php
index 467927911..79713c5c9 100644
--- a/tail.php
+++ b/tail.php
@@ -32,7 +32,7 @@ if ($config['cf_include_tail']) {
     </div>
 </footer>
 
-<?if(!is_mobile()){?>
+<?if(!G4_IS_MOBILE){?>
 <a href="<?=$_SERVER['PHP_SELF'].($_SERVER['QUERY_STRING']?'?'.$_SERVER['QUERY_STRING'].'&amp;':'?').'device=mobile';?>" id="g4s_cng">모바일 버전으로 보기</a>
 <?}?>