How to Block Apktool using Anti-Apktool

Last updated November 20, 2023 by Appdome

This Knowledge Base article describes how to use Appdome’s AI/ML in your CI/CD pipeline to continuously deliver plugins that Block Apktool in Android apps.

What is Apktool?

Apktool is an open-source tool for reverse engineering Android applications. It can be used to extract the contents of an APK file, including the source code and resources. Also, to decode resources to nearly original form and rebuild them after making some modifications.
Apktool has several legitimate uses to both developers and researchers including:
Developers can use this tool to improve the application’s behavior like add new features or to fix bugs, even if the original developer is unknown.

Security researchers and malware analysts can use Apktool to analyze malicious apps and identify vulnerabilities to report the original developers for patching.

Why Should Developers Block Apktool?

Apktool can be used for non-legitimate purposes due to its abilities to extract and decode the contents of an APK file, including the source code and resources, and build crafted application. Therefore, allowing hackers and developers to modify the app and potentially create malicious versions of the app. It can also be used to bypass the license or encryption on paid apps or even bypass detections and protections.

Prerequisites for Using Appdome's Anti-Apktool Plugins:

To use Appdome’s mobile app security build system to Block Apktool , you’ll need:

How to Implement Block Apktool in Android Apps Using Appdome

On Appdome, follow these 3 simple steps to create self-defending Android Apps that Block Apktool without an SDK or gateway:

  1. Designate the Mobile App to be protected.

    1. Upload an app via the Appdome Mobile Defense platform GUI or via Appdome’s DEV-API or CI/CD Plugins.

    2. Android Formats: .apk or .aab
    3. Anti-Apktool is compatible with: Java, JS, C++, C#, Kotlin, Flutter, React Native, Unity, Xamarin, Cordova and other Android apps.
  2. Select the defense: Anti-Apktool.

      1. Create and name the Fusion Set (security template) that will contain the Anti-Apktool feature as shown below:
        fusion set that contains Anti-Apktool

        Figure 1: Fusion Set that will contain the Anti-Apktool feature

      2. Follow the steps in Sections 2.2-2.2.2 of this article to add the Anti-Apktool feature to your Fusion Set via the Appdome Console.

      3. When you enable Anti-Tampering you'll notice that the Fusion Set you created in step 2.1 now bears the icon of the protection category that contains Anti-Apktool.

        Fusion Set applied Anti-Apktool

        Figure 2: Fusion Set that displays the newly added Anti-Apktool protection
        Note: Annotating the Fusion Set to identify the protection(s) selected is optional only (not mandatory).

      4. Open the Fusion Set Detail Summary by clicking the “...” symbol on the far-right corner of the Fusion Set. Copy the Fusion Set ID from the Fusion Set Detail Summary (as shown below): fusion Set Detail Summary image

        Figure 3: Fusion Set Detail Summary

      5. Follow the instructions below to use the Fusion Set ID inside any standard mobile DevOps or CI/CD toolkit like Bitrise, Jenkins, Travis, Team City, Circle CI or other system:
        1. Refer to the Appdome API Reference Guide for API building instructions.
        2. Look for sample APIs in Appdome’s GitHub Repository.
    1. Add the Anti-Apktool feature to your security template.

      1. Navigate to Build > Security tab > Anti-Reverse Engineering section in the Appdome Console.
      2. Toggle On Anti-Tampering > Anti-Apktool.
        Anti-Apktool option

        Figure 4: Selecting Block Apktool

    2. Initiate the build command either by clicking Build My App at the bottom of the Build Workflow (shown in Figure 4) or via your CI/CD as described in Section 2.1.4.
    Congratulations!  The Anti-Apktool protection is now added to the mobile app
  3. Certify the Anti-Apktool feature in Android Apps

    After building Anti-Apktool, Appdome generates a Certified Secure™ certificate to guarantee that the Anti-Apktool protection has been added and is protecting the app. To verify that the Anti-Apktool protection has been added to the mobile app, locate the protection in the Certified Secure™ certificate as shown below: Anti-Apktool shown in Certificate secure

    Figure 5: Certified Secure™ certificate

    Each Certified Secure™ certificate provides DevOps and DevSecOps organizations the entire workflow summary, audit trail of each build, and proof of protection that Anti-Apktool has been added to each Android app. Certified Secure provides instant and in-line DevSecOps compliance certification that Anti-Apktool and other mobile app security features are in each build of the mobile app.

Using Threat-Events™ for Apktool Intelligence and Control in Android Apps

Appdome Threat-Events™ provides consumable in-app mobile app attack intelligence and defense control when Apktool is detected. To consume and use Threat-Events™ for Apktool in Android Apps, use registerReceiver in the Application OnCreate, and the code samples for Threat-Events™ for Apktool shown below.

The specifications and options for Threat-Events™ for Apktool are:

Threat-Event™ Elements Block Apktool Method Detail
Appdome Feature Name Anti-Apktool
Threat-Event Mode
OFF, IN-APP DEFENSE Appdome detects, defends and notifies user (standard OS dialog) using customizable messaging.
ON, IN-APP DETECTION Appdome detects the attack or threat and passes the event in a standard format to the app for processing (app chooses how and when to enforce).
ON, IN-APP DEFENSE Uses Appdome Enforce mode for any attack or threat and passes the event in a standard format to the app for processing (gather intel on attacks and threats without losing any protection).
Certified Secure™ Threat Event Check x
Visible in ThreatScope™ x
Developer Parameters for Blocking Apktool Threat-Event™
Threat-Event NAME
Threat-Event DATA reasonData
Threat-Event CODE reasonCode
Threat-Event REF
Threat-Event SCORE
currentThreatEventScore Current Threat-Event score
threatEventsScore Total Threat-events score
Threat-Event Context Keys
message Message displayed for the user on event
failSafeEnforce Timed enforcement against the identified threat
externalID The external ID of the event which can be listened via Threat Events
osVersion OS version of the current device
deviceModel Current device model
deviceManufacturer The manufacturer of the current device
fusedAppToken The task ID of the Appdome fusion of the currently running app
kernelInfo Info about the kernel: system name, node name, release, version and machine.
carrierPlmn PLMN of the device. Only available for Android devices.
deviceID Current device ID
reasonCode Reason code of the occurred event
buildDate Appdome fusion date of the current application
devicePlatform OS name of the current device
carrierName Carrier name of the current device. Only available for Android.
updatedOSVersion Is the OS version up to date
deviceBrand Brand of the device
deviceBoard Board of the device
buildUser Build user
buildHost Build host
sdkVersion Sdk version
timeZone Time zone
deviceFaceDown Is the device face down
locationLong Location longitude conditioned by location permission
locationLat Location latitude conditioned by location permission
locationState Location state conditioned by location permission
wifiSsid Wifi SSID
wifiSsidPermissionStatus Wifi SSID permission status
threatCode The last six characters of the threat code specify the OS, allowing the Threat Resolution Center to address the attack on the affected device.

With Threat-Events™ enabled (turned ON), Android developers can get detailed attack intelligence and granular defense control in Android applications and create amazing user experiences for all mobile end users when Apktool is detected.


The following is a code sample for native Android apps, which uses all values in the specification above for Anti-Apktool:


Important! Replace all placeholder instances of <Context Key> with the specific name of your threat event context key across all language examples. This is crucial to ensure your code functions correctly with the intended event data. For example, The <Context Key> could be the message, externalID, OS Version, reason code, etc.



Using Appdome, there are no development or coding prerequisites to build secured Android Apps by using Anti-Apktool. There is no SDK and no library to code or implement in the app and no gateway to deploy in your network. All protections are built into each app and the resulting app is self-defending and self-protecting.

Releasing and Publishing Mobile Apps with Anti-Apktool

After successfully securing your app by using Appdome, there are several available options to complete your project, depending on your app lifecycle or workflow. These include:

Related Articles:

How Do I Learn More?

If you have any questions, please send them our way at support.appdome.com or via the chat window on the Appdome platform.

Thank you!

Thanks for visiting Appdome! Our mission is to secure every app on the planet by making mobile app security easy. We hope we’re living up to the mission with your project.

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