How to Encrypt Java Strings in Android Apps Using AI

Last updated February 23, 2025 by Appdome

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

What Is Encrypting Java Strings?

In Android apps, strings often store sensitive data such as API keys, credentials, tokens, or URLs. Without encryption, these strings are easily accessible through tools like JADX or Smali, exposing them to unauthorized access and misuse. Encrypting Java strings prevents attackers from viewing and exploiting this sensitive data. Implementing string encryption aligns with PCI DSS and GDPR compliance by ensuring that sensitive information remains protected, reducing the risk of exposure during reverse engineering.

How Appdome Protects Mobile Apps With Encrypting Java Strings?

Appdome’s dynamic Encrypt Java Strings plugin automatically encrypts all hardcoded strings in Java-based Android apps, ensuring that sensitive data cannot be extracted through static analysis. The plugin applies encryption and obfuscation techniques to conceal plaintext strings from decompilers and analysis tools. This ensures that sensitive data remains protected in the application’s code, strengthening overall security without requiring developer modifications.

Prerequisites for Using Appdome's Encrypt Strings Plugins:

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

How to Implement Encrypt Strings in Android Apps Using Appdome

On Appdome, follow these 3 simple steps to create self-defending Android Apps that Encrypt Strings 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. Encrypt Strings is compatible with: Java, JS, C++, C#, Kotlin, Flutter, React Native, Unity, Xamarin, Cordova and other Android apps.
  2. Select the defense: Encrypt Strings.

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

        Figure 1: Fusion Set that will contain the Encrypt Strings feature

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

      3. When you select the Encrypt Strings you'll notice that the Fusion Set you created in step 2.1 now bears the icon of the protection category that contains Encrypt Strings.

        Fusion Set applied Encrypt Strings

        Figure 2: Fusion Set that displays the newly added Encrypt Strings 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 Encrypt Strings feature to your security template.

      1. Navigate to Build > Security tab > TOTALData™ Encryption section in the Appdome Console.
      2. Toggle On > Encrypt Strings.
        Encrypt Strings option

        Figure 4: Selecting Encrypt Strings

        Note: The Appdome Platform displays the Mobile Operation Systems supported by each defense in real-time. For more details, see our OS Support Policy KB.

      3. Configure the User Experience Options for Encrypt Strings:
        With Threat-Events™ OFF, Appdome provides several user experience options for mobile brands and developers.
        1. App Compromise Notification: Customize the pop-up or toast Appdome uses to notify the user when a threat is present while using the protected mobile app.
        2. Short message Option. This is available for mobile devices that allow a banner notification for security events.
        3. Localized Message Option. Allows Appdome users to support global languages in security notifications.

          Localized Message

          Figure 5: Default User Experience Options for Appdome’s Strings

        4. Encrypt Strings Threat Code™. Appdome uses AI/ML to generate a unique code each time Encrypt Strings is triggered by an active threat on the mobile device. Use the code in Appdome Threat Resolution Center™ to help end users identify, find and resolve active threats on the personal mobile devices.
      4. Extra Configuration with Encrypt Strings:
        1. Encrypt Resources

          Encrypt all Android application assets.

    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 Encrypt Strings protection is now added to the mobile app
  3. Certify the Encrypt Strings feature in Android Apps

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

    Figure 6: 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 Encrypt Strings has been added to each Android app. Certified Secure provides instant and in-line DevSecOps compliance certification that Encrypt Strings and other mobile app security features are in each build of the mobile app.

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

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

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

Threat-Event™ Elements Encrypt Strings Method Detail
Appdome Feature Name Encrypt Strings
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 Encrypting Strings 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 Strings are detected.


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


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 Encrypt Strings. 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 Encrypt Strings

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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