diff --git a/app/build.gradle b/app/build.gradle
index 6c4db91d..ad4c455c 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -9,8 +9,8 @@ android {
         applicationId "com.stardust.scriptdroid"
         minSdkVersion 17
         targetSdkVersion 23
-        versionCode 161
-        versionName "2.0.16 Alpha4"
+        versionCode 162
+        versionName "2.0.16 Beta2"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         multiDexEnabled true
         ndk {
diff --git a/app/src/main/java/com/stardust/scriptdroid/ui/main/MainActivity.java b/app/src/main/java/com/stardust/scriptdroid/ui/main/MainActivity.java
index 4895be0a..38ad3eef 100644
--- a/app/src/main/java/com/stardust/scriptdroid/ui/main/MainActivity.java
+++ b/app/src/main/java/com/stardust/scriptdroid/ui/main/MainActivity.java
@@ -15,6 +15,7 @@ import android.support.v4.view.ViewPager;
 import android.support.v4.widget.DrawerLayout;
 import android.support.v7.app.ActionBarDrawerToggle;
 import android.support.v7.widget.Toolbar;
+import android.util.Log;
 import android.view.Gravity;
 import android.view.View;
 import android.widget.ImageView;
@@ -38,6 +39,7 @@ import com.stardust.scriptdroid.script.ScriptFile;
 import com.stardust.scriptdroid.script.StorageScriptProvider;
 import com.stardust.scriptdroid.ui.common.ScriptOperations;
 import com.stardust.scriptdroid.ui.main.task.TaskManagerFragment_;
+import com.stardust.util.DeveloperUtils;
 import com.stardust.util.IntentExtras;
 import com.stardust.view.accessibility.AccessibilityService;
 import com.stardust.scriptdroid.tool.AccessibilityServiceTool;
@@ -304,6 +306,13 @@ public class MainActivity extends BaseActivity implements OnActivityResultDelega
         StorageScriptProvider.getDefault().notifyStoragePermissionGranted();
     }
 
+    @Override
+    protected void onStart() {
+        super.onStart();
+        if (!DeveloperUtils.checkSignature(this)) {
+            finish();
+        }
+    }
 
     @Override
     protected void onDestroy() {
diff --git a/common/src/main/java/com/stardust/util/DeveloperUtils.java b/common/src/main/java/com/stardust/util/DeveloperUtils.java
index 66add949..19e78dfd 100644
--- a/common/src/main/java/com/stardust/util/DeveloperUtils.java
+++ b/common/src/main/java/com/stardust/util/DeveloperUtils.java
@@ -1,7 +1,13 @@
 package com.stardust.util;
 
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.Signature;
 import android.support.annotation.Nullable;
 
+import com.stardust.BuildConfig;
+
 /**
  * Created by Stardust on 2017/4/5.
  */
@@ -9,6 +15,7 @@ import android.support.annotation.Nullable;
 public class DeveloperUtils {
 
     private static final String PACKAGE_NAME = "com.stardust.scriptdroid";
+    private static final String SIGNATURE = "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";
 
     public static void ensureRunningPackageNotSelf(@Nullable String runningPackage) {
         if (PACKAGE_NAME.equals(runningPackage)) {
@@ -19,4 +26,30 @@ public class DeveloperUtils {
     public static boolean isSelfPackage(@Nullable String runningPackage) {
         return PACKAGE_NAME.equals(runningPackage);
     }
+
+    public static String getSignature(Context context) {
+        try {
+            PackageInfo packageInfo = context.getPackageManager().getPackageInfo(context.getPackageName(), PackageManager.GET_SIGNATURES);
+            Signature[] signatures = packageInfo.signatures;
+            StringBuilder builder = new StringBuilder();
+            for (Signature signature : signatures) {
+                builder.append(signature.toCharsString());
+            }
+            return builder.toString();
+        } catch (PackageManager.NameNotFoundException e) {
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+    /**
+     * 此方法仅防止那些不会改源码直接用apk编辑器修改应用内字符串(QQ群号)等的恶意用户行为。
+     * 为了开源社区的发展，请善用源码:-)
+     */
+    public static boolean checkSignature(Context context) {
+        if (BuildConfig.DEBUG)
+            return true;
+        return SIGNATURE.equals(getSignature(context));
+    }
+
 }