diff --git a/.env b/.env
index 37205de..f01c5db 100644
--- a/.env
+++ b/.env
@@ -1,4 +1,4 @@
-# iOS 6620
+# iOS 6670
 APP_KEY=27eb53fc9058f8c3
 APP_SECRET=c2ed53a74eeefe3cf99fbd01d8c9c375
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ad14e35..748925d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Release Notes
 
+## v0.7.3 (2018-04-28)
+
+### Added
+- 新增帐号别名参数
+
+### Changed
+- 更新模拟客户端版本 (iOS 6670)
+- 修正环境变量刷新逻辑
+
+### Fixed
+- 修复部分语法错误
+- 修复错误信息回调函数逻辑错误
+
+
 ## v0.7.2 (2018-04-22)
 
 ### Added
diff --git a/composer.json b/composer.json
index e63f92d..40ca159 100644
--- a/composer.json
+++ b/composer.json
@@ -1,6 +1,5 @@
 {
     "name": "metowolf/bilibili",
-    "version": "0.7.0",
     "description": "B 站自动领瓜子、直播挂机脚本",
     "type": "project",
     "require": {
diff --git a/composer.lock b/composer.lock
index b82e43a..9c73f4e 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "3982e326cdc952573152cb10b6989b40",
+    "content-hash": "754a5e797e44122a108386a2bed581fb",
     "packages": [
         {
             "name": "bramus/ansi-php",
diff --git a/src/Curl.php b/src/Curl.php
index 82ebf4f..72530a9 100644
--- a/src/Curl.php
+++ b/src/Curl.php
@@ -21,7 +21,7 @@ class Curl
             'Accept-Language' => 'zh-cn',
             'Connection'      => 'keep-alive',
             'Content-Type'    => 'application/x-www-form-urlencoded',
-            'User-Agent'      => 'User-Agent: bili-universal/6620 CFNetwork/897.15 Darwin/17.5.0',
+            'User-Agent'      => 'User-Agent: bili-universal/6670 CFNetwork/897.15 Darwin/17.5.0',
     );
 
     public static function post($url, $payload = null)
diff --git a/src/Log.php b/src/Log.php
index ce33cc1..ec0d6a5 100644
--- a/src/Log.php
+++ b/src/Log.php
@@ -3,7 +3,7 @@
 /*!
  * metowolf BilibiliHelper
  * https://i-meto.com/
- * Version 18.04.21
+ * Version 18.04.28
  *
  * Copyright 2018, laverboy & metowolf
  * https://gist.github.com/laverboy/fd0a32e9e4e9fbbf9584
@@ -85,7 +85,7 @@ public static function error($message, array $context = [])
 
     public static function callback($levelId, $level, $message)
     {
-        $callback_level = empty(getenv('APP_CALLBACK_LEVEL')) ? (Logger::ERROR) : intval(getenv('APP_CALLBACK_LEVEL'));
+        $callback_level = (getenv('APP_CALLBACK_LEVEL') === false) ? (Logger::ERROR) : intval(getenv('APP_CALLBACK_LEVEL'));
         if ($levelId >= $callback_level) {
             $url = str_replace('{account}', self::prefix(), getenv('APP_CALLBACK'));
             $url = str_replace('{level}', $level, $url);
diff --git a/src/Login.php b/src/Login.php
index 3b8ca6b..b966cf8 100644
--- a/src/Login.php
+++ b/src/Login.php
@@ -22,7 +22,7 @@ class Login
     public static function run()
     {
         Log::info('正在装载终端');
-        if (empty(getenv('ACCESS_TOKEN'))) {
+        if (getenv('ACCESS_TOKEN') == "") {
             Log::info('令牌载入中...');
             self::login();
         }
@@ -99,12 +99,8 @@ public static function refresh()
         Log::info('令牌生成完毕!');
 
         $access_token = $data['data']['access_token'];
-        self::writeNewEnvironmentFileWith('ACCESS_TOKEN', $access_token);
-        Log::info(' > access token: '.$access_token);
-
         $refresh_token = $data['data']['refresh_token'];
-        self::writeNewEnvironmentFileWith('REFRESH_TOKEN', $refresh_token);
-        Log::info(' > refresh token: '.$refresh_token);
+        self::overload($access_token, $refresh_token);
 
         return true;
     }
@@ -160,14 +156,21 @@ protected static function login()
         Log::info('令牌获取成功!');
 
         $access_token = $data['data']['token_info']['access_token'];
+        $refresh_token = $data['data']['token_info']['refresh_token'];
+        self::overload($access_token, $refresh_token);
+
+        return;
+    }
+
+    protected static function overload($access_token, $refresh_token)
+    {
         self::writeNewEnvironmentFileWith('ACCESS_TOKEN', $access_token);
+        putenv('ACCESS_TOKEN='.$access_token);
         Log::info(' > access token: '.$access_token);
 
-        $refresh_token = $data['data']['token_info']['refresh_token'];
         self::writeNewEnvironmentFileWith('REFRESH_TOKEN', $refresh_token);
+        putenv('REFRESH_TOKEN='.$refresh_token);
         Log::info(' > refresh token: '.$refresh_token);
-
-        return;
     }
 
     protected static function writeNewEnvironmentFileWith($key, $value)
diff --git a/src/Sign.php b/src/Sign.php
index 0355c97..eccbc88 100644
--- a/src/Sign.php
+++ b/src/Sign.php
@@ -19,8 +19,7 @@ public static function api($payload)
             'access_key' => getenv('ACCESS_TOKEN'),
             'actionKey' => 'appkey',
             'appkey' => getenv('APP_KEY'),
-            'appver' => '6620',
-            'build' => '6620',
+            'build' => '6670',
             'device' => 'phone',
             'mobi_app' => 'iphone',
             'platform' => 'ios',