diff --git a/app/src/main/java/org/itxtech/daedalus/Daedalus.java b/app/src/main/java/org/itxtech/daedalus/Daedalus.java
index 8aeff92..2809d9b 100644
--- a/app/src/main/java/org/itxtech/daedalus/Daedalus.java
+++ b/app/src/main/java/org/itxtech/daedalus/Daedalus.java
@@ -4,10 +4,12 @@ import android.app.ActivityManager;
 import android.app.Application;
 import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.content.pm.ShortcutInfo;
 import android.content.pm.ShortcutManager;
 import android.graphics.drawable.Icon;
 import android.os.Build;
+import android.preference.PreferenceManager;
 import android.util.Log;
 import org.itxtech.daedalus.activity.MainActivity;
 import org.itxtech.daedalus.service.DaedalusVpnService;
@@ -28,7 +30,7 @@ import java.util.List;
  * the Free Software Foundation, version 3.
  */
 public class Daedalus extends Application {
-    public static final String SHORTCUT_ID_ACTIVATE = "activate";
+    private static final String SHORTCUT_ID_ACTIVATE = "shortcut_activate";
 
     public static final List<DnsServer> DNS_SERVERS = new ArrayList<DnsServer>() {{
         add(new DnsServer("0", "113.107.249.56", R.string.server_north_china));
@@ -45,14 +47,26 @@ public class Daedalus extends Application {
     };
 
     private static Daedalus instance = null;
+    private static SharedPreferences prefs;
 
     @Override
     public void onCreate() {
         super.onCreate();
 
+        initConfig();
+
         instance = this;
     }
 
+    private void initConfig() {
+        PreferenceManager.setDefaultValues(this, R.xml.perf_settings, false);
+        prefs = PreferenceManager.getDefaultSharedPreferences(this);
+    }
+
+    public static SharedPreferences getPrefs() {
+        return prefs;
+    }
+
     @Override
     public void onTerminate() {
         super.onTerminate();
diff --git a/app/src/main/java/org/itxtech/daedalus/activity/MainActivity.java b/app/src/main/java/org/itxtech/daedalus/activity/MainActivity.java
index 28deee4..d07e26b 100644
--- a/app/src/main/java/org/itxtech/daedalus/activity/MainActivity.java
+++ b/app/src/main/java/org/itxtech/daedalus/activity/MainActivity.java
@@ -3,10 +3,8 @@ package org.itxtech.daedalus.activity;
 import android.app.ActivityManager;
 import android.content.Context;
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.net.VpnService;
 import android.os.Bundle;
-import android.preference.PreferenceManager;
 import android.support.design.widget.FloatingActionButton;
 import android.support.v7.app.AppCompatActivity;
 import android.util.Log;
@@ -38,7 +36,6 @@ public class MainActivity extends AppCompatActivity {
     public static final int LAUNCH_ACTION_DEACTIVATE = 2;
 
     private static MainActivity instance = null;
-    private SharedPreferences prefs;
 
     public static MainActivity getInstance() {
         return instance;
@@ -50,8 +47,6 @@ public class MainActivity extends AppCompatActivity {
 
         instance = this;
 
-        initConfig();
-
         setContentView(R.layout.activity_main);
         /*Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
         setSupportActionBar(toolbar);*/
@@ -152,11 +147,6 @@ public class MainActivity extends AppCompatActivity {
         updateUserInterface();
     }
 
-    private void initConfig() {
-        PreferenceManager.setDefaultValues(this, R.xml.perf_settings, false);
-        prefs = PreferenceManager.getDefaultSharedPreferences(this);
-    }
-
     private void activateService() {
         Intent intent = VpnService.prepare(this);
         if (intent != null) {
@@ -188,8 +178,8 @@ public class MainActivity extends AppCompatActivity {
 
     protected void onActivityResult(int request, int result, Intent data) {
         if (result == RESULT_OK) {
-            DaedalusVpnService.primaryServer = DnsServer.getDnsServerAddressById(prefs.getString("primary_server", "0"));
-            DaedalusVpnService.secondaryServer = DnsServer.getDnsServerAddressById(prefs.getString("secondary_server", "1"));
+            DaedalusVpnService.primaryServer = DnsServer.getDnsServerAddressById(Daedalus.getPrefs().getString("primary_server", "0"));
+            DaedalusVpnService.secondaryServer = DnsServer.getDnsServerAddressById(Daedalus.getPrefs().getString("secondary_server", "1"));
 
             startService(getServiceIntent().setAction(DaedalusVpnService.ACTION_ACTIVATE));
 
diff --git a/app/src/main/java/org/itxtech/daedalus/activity/ServerTestActivity.java b/app/src/main/java/org/itxtech/daedalus/activity/ServerTestActivity.java
index 2e78c84..da7b2ed 100644
--- a/app/src/main/java/org/itxtech/daedalus/activity/ServerTestActivity.java
+++ b/app/src/main/java/org/itxtech/daedalus/activity/ServerTestActivity.java
@@ -21,6 +21,7 @@ import org.itxtech.daedalus.R;
 import org.itxtech.daedalus.util.DnsServer;
 
 import java.net.InetAddress;
+import java.util.ArrayList;
 import java.util.Random;
 import java.util.Set;
 
@@ -84,7 +85,15 @@ public class ServerTestActivity extends AppCompatActivity {
                                     testDomain = Daedalus.DEFAULT_TEST_DOMAINS[0];
                                 }
                                 StringBuilder testText = new StringBuilder();
-                                String[] dnsServers = {DnsServer.getDnsServerAddressByStringDescription(context, spinnerServerChoice.getSelectedItem().toString()), "114.114.114.114", "8.8.8.8"};
+                                ArrayList<String> dnsServers = new ArrayList<String>() {{
+                                    add(DnsServer.getDnsServerAddressByStringDescription(context, spinnerServerChoice.getSelectedItem().toString()));
+                                    String servers = Daedalus.getPrefs().getString("dns_test_servers", "");
+                                    if (!servers.equals("")) {
+                                        for (String server : servers.split(",")) {
+                                            add(server);
+                                        }
+                                    }
+                                }};
                                 DNSClient client = new DNSClient(null);
                                 for (String dnsServer : dnsServers) {
                                     testText = testServer(client, dnsServer, testDomain, testText);
diff --git a/app/src/main/java/org/itxtech/daedalus/receiver/BootBroadcastReceiver.java b/app/src/main/java/org/itxtech/daedalus/receiver/BootBroadcastReceiver.java
index de9f343..fdc51b8 100644
--- a/app/src/main/java/org/itxtech/daedalus/receiver/BootBroadcastReceiver.java
+++ b/app/src/main/java/org/itxtech/daedalus/receiver/BootBroadcastReceiver.java
@@ -3,12 +3,9 @@ package org.itxtech.daedalus.receiver;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.net.VpnService;
-import android.preference.PreferenceManager;
 import android.util.Log;
 import org.itxtech.daedalus.Daedalus;
-import org.itxtech.daedalus.R;
 import org.itxtech.daedalus.service.DaedalusVpnService;
 import org.itxtech.daedalus.util.DnsServer;
 
@@ -25,17 +22,15 @@ import org.itxtech.daedalus.util.DnsServer;
 public class BootBroadcastReceiver extends BroadcastReceiver {
     @Override
     public void onReceive(Context context, Intent intent) {
-        PreferenceManager.setDefaultValues(context, R.xml.perf_settings, false);
-        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
-        if (prefs.getBoolean("settings_boot", false)) {
+        if (Daedalus.getPrefs().getBoolean("settings_boot", false)) {
 
             Intent vIntent = VpnService.prepare(context);
             if (vIntent != null) {
                 context.startActivity(vIntent);
             }
 
-            DaedalusVpnService.primaryServer = DnsServer.getDnsServerAddressById(prefs.getString("primary_server", "0"));
-            DaedalusVpnService.secondaryServer = DnsServer.getDnsServerAddressById(prefs.getString("secondary_server", "1"));
+            DaedalusVpnService.primaryServer = DnsServer.getDnsServerAddressById(Daedalus.getPrefs().getString("primary_server", "0"));
+            DaedalusVpnService.secondaryServer = DnsServer.getDnsServerAddressById(Daedalus.getPrefs().getString("secondary_server", "1"));
 
             context.startService((new Intent(context, DaedalusVpnService.class)).setAction(DaedalusVpnService.ACTION_ACTIVATE));
 
diff --git a/app/src/main/res/values-zh/strings.xml b/app/src/main/res/values-zh/strings.xml
index 84e21eb..6df0e02 100644
--- a/app/src/main/res/values-zh/strings.xml
+++ b/app/src/main/res/values-zh/strings.xml
@@ -37,4 +37,5 @@
     <string name="notice_legacy_api">当前 Android API 无法支持所有功能。</string>
     <string name="settings_issue_tracker">提交反馈</string>
     <string name="settings_issue_summary">前往 GitHub 提交问题反馈。</string>
+    <string name="settings_dns_test_servers">DNS 测试服务器</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 791dbc8..e4bb276 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -37,4 +37,5 @@
     <string name="notice_legacy_api">The current Android API can not support all the features.</string>
     <string name="settings_issue_tracker">Issue tracker</string>
     <string name="settings_issue_summary">Submit an issue in GitHub Issues page.</string>
+    <string name="settings_dns_test_servers">DNS test servers</string>
 </resources>
diff --git a/app/src/main/res/xml/perf_settings.xml b/app/src/main/res/xml/perf_settings.xml
index 0761d27..502cd39 100644
--- a/app/src/main/res/xml/perf_settings.xml
+++ b/app/src/main/res/xml/perf_settings.xml
@@ -16,6 +16,12 @@
                 android:title="@string/secondary_server"
                 android:defaultValue="1">
         </ListPreference>
+        <EditTextPreference
+                android:key="dns_test_servers"
+                android:defaultValue="114.114.114.114,8.8.8.8"
+                android:selectAllOnFocus="true"
+                android:singleLine="true"
+                android:title="@string/settings_dns_test_servers"/>
     </PreferenceCategory>
     <PreferenceCategory
             android:key="settings_system"