# [Set up the app for debugging with MTE](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/how-to-3/)

## In this learning path

- [Introduction](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/)
- [Background](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/how-to-1/)
- [Implement memory safety bugs with the Android app](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/how-to-2/)
- [Set up the app for debugging with MTE](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/how-to-3/)
- [Debug in Android Studio with MTE](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/how-to-4/)
- [Next Steps](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/_next-steps/)

## Enabling MTE in the Android project

There are different ways to enable MTE in Android projects.

For a detailed description, see [Memory safety](https://source.android.com/docs/security/test/memory-safety).

You can use the application manifest to enable MTE.

To open the application manifest, switch the project view to **Project Files** and expand `app->src->main->res` folders as shown in the picture below. Double-click on the `AndroidManifes.xml` file to open it.

![Android Manifest file path.](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/debugging_with_mte_on_pixel8/pictures/04_android_manifest_path.png)

Here is the manifest file:

```xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.mte_test">

    <application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.AppCompat.Light.NoActionBar"
        tools:targetApi="31"
        android:memtagMode="sync"
        tools:ignore="MissingPrefix">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>
```

The line below enables MTE in *sync* mode in the application.

```xml
android:memtagMode="sync"
```

The attribute *memTagMode* can have the following values: *off*, *sync*, *async*, and *asymm*.

If the *android:memtagMode* attribute is not specified, then MTE is disabled.

This Learning Path demonstrates the *sync* value of *memtagMode* attribute.

In synchronous mode (*sync*), a mismatch between the tag in the address and the tag in memory causes the processor to abort execution immediately. It terminates the process with SIGSEGV (code SEGV_MTESERR), which is a synchronous exception. This identifies the precise instruction and address that caused the failure.

*Sync* mode is recommended when debugging your application.

You can find detailed information on MTE modes in the [MTE Guide for Android OS](https://documentation-service.arm.com/static/660d6857aec7154a17ee1c5f?token=).

The last step is to enable MTE in the phone settings.

For this, follow the indications provided in the Learning Path [Memory Tagging Extension on Google Pixel 8](https://learn.arm.com/learning-paths/mobile-graphics-and-gaming/mte_on_pixel8/).