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Accessibility Insights for AndroidTM Service

Build Status

Accessibility Insights for Android Service is a service for Android that helps in assessing the accessibility of Android applications.

Building the code


  • Download and install Android Studio

    • If you plan on using Android Studio's emulator, make sure "Android Virtual Device" is checked in the download setup dialog
    • Selecting the standard installation (recommended) will also install Android SDK tools
  • Emulator (optional, if not using a physical device):

    • From Android Studio, start Android Virtual Device (AVD) Manager: Tools > AVD Manager
    • Select Create Virtual Device. This may require downloading the selected system image. If possible, select a newer device, such as Pixel 3 API 29 .

Note: We do not recommend using a personal Android device for testing and development; we recommend using a testing device or emulator. Software under development may not yet be fully secure, and many development tools require permissions that could present a potential risk to your device and data.

Setup (Windows, Linux, Mac)

While the instructions for Windows, Linux, and Mac are the same, the instructions below are written with Windows-style file paths.

  1. Fork and clone the repository

  2. Open the project with Android Studio

    • This must be the Android project AccessibilityInsightsForAndroidService inside the repo, not the top-level accessibility-insights-for-android-service folder
  3. The project will automatically sync and build

  4. Change the launch options in Android Studio:

    • Under the Run menu, select Edit configurations...
      • Ensure that the app is selected in the left navigation pane
      • Under General > Launch Options, change Launch from "Default Activity" to "Nothing"
      • Select Apply, then Ok
  5. Run the app from Android Studio (this will install the APK onto the emulator). The app won't show up in the list of programs--it shows up as a downloaded accessibility service. It will be off by default. To activate it:

    • Open the Settings app in the emulator. If you have trouble opening the emulator, see Unable to start emulator under Known Issues below
    • Scroll down and select Accessibility
    • Select "Accessibility Insights for Android Service" under Downloaded services
    • Toggle on Use service to enable the service
    • Select Allow on the resulting dialog to grant the necessary permissions
    • An "Exposing sensitive info during casting/recording" dialog should appear. Select Start now

Triggering requests in adb

While the service is running, you can manually trigger requests by invoking the following adb shell content commands:

  • Config

    • adb shell content read --uri content://
    • Returned data includes:
      • deviceName - the name of the device from the Android Build.MODEL
      • packageName - the package the associated root AccessibilityInfoNode comes from
      • serviceVersion - the version of the service
  • Raw Axe and ATFA Results (results version 2)

    • adb shell content read --uri content://
    • Returned data includes:
      • AxeResults
        • axeConf - the set AxeConf object listing which rules will run
        • axeContext - the Context axe-android is running the rules on
          • axeDevice - the device the context was built on
          • axeEventStream - the AccessibilityEvent Stream since the last view refresh
          • axeMetadata
            • analysisTimestamp - the timestamp at time of analysis
            • appIdentifier - the Android PackageName
            • axeVersion - implementation version of package
            • screenTitle - title of current screen
          • axeView - the serializable view hierarchy at the time the context was built
          • screenshot - the screenshot at the time the Context was built (this will display as a wall of text BitMap in the browser)
        • axeRuleResults - an array of AxeRuleResult objects. Each has:
          • axeViewId - the ID of the view it's associated with (corresponds to a view listed above in axeContext)
          • impact - the severity of the issue
          • props - the properties used in determining the outcome
          • ruleId - the ID of the rule
          • ruleSummary - short summary of the rule.
          • status - the status of the rule (PASS, FAIL, etc)
      • ATFARules - an array of AccessibilityHierarchyCheck objects. Each has:
        • class - the name of the class for the check
        • titleMessage - the human-readable title of the check
        • category - the type of accessibility check (see Category)
        • helpUrl - the URL for a help article related to the check
        • resultIdsAndMetadata - a map providing possible result IDs and additional metadata about the check
      • ATFAResults- an array of AccessibilityHierarchyCheckResult objects. Each has:
        • AccessibilityHierarchyCheckResult.element - a ViewHierarchyElement object corresponding to the result
        • AccessibilityHierarchyCheckResult.resultId - an ID grouping all results from a single class
        • AccessibilityCheckResult.checkClass - the name of the class for the check which reported the result
        • AccessibilityCheckResult.type - the status of the result (see AccessibilityCheckResultType)
        • AccessibilityHierarchyCheckResult.metadata - an object which implements ResultMetadata containing additional information about the result

Known issues

Gradle sync fails

Restarting Android Studio and waiting for everything to load before building the project could solve the issue

  • Error message: Cannot find symbol.

    • Sometimes the issue is caused because the file path exceeded the maximum number of characters allowed, so you could try to shorten the path by changing the location of the project folder on your computer.
SDK setup issues
  • Error message: Failed to install the following Android SDK packages as some licences have not been accepted.

    • Select the "Install missing SDK package(s)" link at the end of the error message. Follow the prompt to agree to license terms and install missing SDK tools
Unable to start emulator
  • (Windows) Error message: Intel HAXM is required to run this AVD. VT-x is disabled in BIOS. Enable VT-x in your BIOS security settings (refer to documentation for your computer).

    • Virtualization might not be enabled on your computer. To check if it is, open Task Manager and select the Performance tab. If "Virtualization" is disabled, follow these instructions to enable virtualization in your BIOS. The option to enable virtualization might be under "Security settings"

    • Sometimes the issue is caused by Hyper-V blocking other virtualization apps, so you could also try to turn off Hyper-V.

  • (Linux) Error message: KVM is required to run this AVD. /dev/kvm device: permission denied. Grant current user access to /dev/kvm

    • Open a Terminal window and run the following:
      sudo apt install qemu-kvm
      sudo adduser $USER kvm
    • Restart your machine

Migrating from version 1.x

  • The communication protocol in 1.x was "use adb forward to access an http server on the device". This method has been removed in 2.x and replaced with the adb shell content commands listed above.
  • The "v1" results API (which included only Axe results and not ATFA results) was removed in 2.x and replaced with the v2 results API which also includes ATFA results.

Reporting security vulnerabilities

If you believe you have found a security vulnerability in this project, please follow these steps to report it. For more information on how vulnerabilities are disclosed, see Coordinated Vulnerability Disclosure.


This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft's Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.


All contributions are welcome! Please read through our guidelines on contributions to this project.

Code of Conduct

Please read through our Code of Conduct to this project.

Android is a trademark of Google LLC.