diff --git a/public/assets/wechat/app.html b/public/assets/wechat/app.html
index d49caedd5..5ab1dcb5a 100644
--- a/public/assets/wechat/app.html
+++ b/public/assets/wechat/app.html
@@ -39,6 +39,7 @@
 <script src="/javascripts/wechat/directives/ellipsis.js"></script>
 <script src="/javascripts/wechat/directives/input_focus.js"></script>
 <script src="/javascripts/wechat/directives/at_delete_link.js"></script>
+<script src="/javascripts/wechat/directives/iphone_recognize.js"></script>
 <script src="/javascripts/wechat/controllers/reg.js"></script>
 <script src="/javascripts/wechat/controllers/login.js"></script>
 <script src="/javascripts/wechat/controllers/activity.js"></script>
diff --git a/public/assets/wechat/blog_detail.html b/public/assets/wechat/blog_detail.html
index c1e2fd2fd..daeec493d 100644
--- a/public/assets/wechat/blog_detail.html
+++ b/public/assets/wechat/blog_detail.html
@@ -69,7 +69,7 @@
                 </div>
             </div>
 
-            <div ng-if="!blog.locked" id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div ng-if="!blog.locked" id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/course_discussion.html b/public/assets/wechat/course_discussion.html
index 3d7444c95..78a3fa0b7 100644
--- a/public/assets/wechat/course_discussion.html
+++ b/public/assets/wechat/course_discussion.html
@@ -66,7 +66,7 @@
                     </div>
                 </div>
 
-                <div ng-if="!discussion.locked" id="post_input_1" class="post-input-wrap post-box-shadow">
+                <div ng-if="!discussion.locked" id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                     <div class="post-reply-row border-bottom-none">
                         <div class="post-input-container">
                             <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/course_notice.html b/public/assets/wechat/course_notice.html
index 95eeda60b..f991656b4 100644
--- a/public/assets/wechat/course_notice.html
+++ b/public/assets/wechat/course_notice.html
@@ -46,7 +46,7 @@
                 </div>
             </div>
 
-            <div id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/homework_detail.html b/public/assets/wechat/homework_detail.html
index 77aa0a48d..6ead09e69 100644
--- a/public/assets/wechat/homework_detail.html
+++ b/public/assets/wechat/homework_detail.html
@@ -70,7 +70,7 @@
                 </div>
             </div>
 
-            <div id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/issue_detail.html b/public/assets/wechat/issue_detail.html
index 14df1cfb1..b4d39d04e 100644
--- a/public/assets/wechat/issue_detail.html
+++ b/public/assets/wechat/issue_detail.html
@@ -52,7 +52,7 @@
                 </div>
             </div>
 
-            <div id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/jour_message_detail.html b/public/assets/wechat/jour_message_detail.html
index b94bca8b2..41f7290e5 100644
--- a/public/assets/wechat/jour_message_detail.html
+++ b/public/assets/wechat/jour_message_detail.html
@@ -65,7 +65,7 @@
                 </div>
             </div>
 
-            <div id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/assets/wechat/project_discussion.html b/public/assets/wechat/project_discussion.html
index fef0a2f6e..4557ba55f 100644
--- a/public/assets/wechat/project_discussion.html
+++ b/public/assets/wechat/project_discussion.html
@@ -65,7 +65,7 @@
                     <div id="more_reply" class="more-events mt10" ng-click="showMoreReply(0,discussion);">更多</div>
                 </div>
             </div>
-            <div ng-if="!discussion.locked" id="post_input_1" class="post-input-wrap post-box-shadow">
+            <div ng-if="!discussion.locked" id="post_input_1" class="post-input-wrap post-box-shadow" iphone-recognize>
                 <div class="post-reply-row border-bottom-none">
                     <div class="post-input-container">
                         <div class="copy-input-container"><textarea class="copy-input"></textarea></div>
diff --git a/public/javascripts/wechat/directives/iphone_recognize.js b/public/javascripts/wechat/directives/iphone_recognize.js
new file mode 100644
index 000000000..0d435e1a2
--- /dev/null
+++ b/public/javascripts/wechat/directives/iphone_recognize.js
@@ -0,0 +1,17 @@
+/**
+ * Created by ttang on 2016/8/22.
+ */
+app.directive('iphoneRecognize',function(){
+    return{
+        restrict: 'A',
+        scope: {},
+        link: function(scope, element){
+            var userAgent = navigator.userAgent;
+            if (/ipad|iphone|mac/i.test(navigator.userAgent)){
+                element.css({"position":"relative","padding":"1px 0"});
+                $(".post-wrapper").css("margin-bottom","0");
+                $("#all_homework_reply").css("margin-bottom","0");
+            }
+        }
+    }
+});
\ No newline at end of file