Android Permissions Security

Video

Every Android app runs in a limited-access sandbox. If your app needs to use resources or information outside of its own sandbox, you can declare a runtime permission and set up a permission request that provides this access. These steps are part of the workflow for using permissions.

If you declare any dangerous permissions, and if your app is installed on a device that runs Android 6.0 (API level 23) or higher, you must request the dangerous permissions at runtime by following the steps in this guide.

If you don't declare any dangerous permissions, or if your app is installed on a device that runs Android 5.1 (API level 22) or lower, the permissions are automatically granted, and you don't need to complete any of the remaining steps on this page.

[!NOTE] Note: Some permissions guard access to system resources that are particularly sensitive or are not directly related to user privacy. There's a different process for requesting these special permissions.

Basic principles

The basic principles for requesting permissions at runtime are as follows:

• Ask for a permission in context, when the user starts to interact with the feature that requires it.

• Don't block the user. Always provide the option to cancel an educational UI flow, such as a flow that explains the rationale for requesting permissions.

• If the user denies or revokes a permission that a feature needs, gracefully degrade your app so that the user can continue using your app, possibly by disabling the feature that requires the permission.

• Don't assume any system behavior. For example, don't assume that permissions appear in the same permission group. A permission group merely helps the system minimize the number of system dialogs that are presented to the user when an app requests closely related permissions.

Workflow for requesting permissions

Before you declare and request runtime permissions in your app, evaluate whether your app needs to do so. You can fulfill many use cases in your app, such as taking photos, pausing media playback, and displaying relevant ads, without needing to declare any permissions.

If you conclude that your app needs to declare and request runtime permissions, complete these steps:

1. Declare the permissions your app might need to request in your app's manifest file.

2. Design your app's user experience (UX) so that specific actions in your app are associated with specific runtime permissions. Let users know which actions might require them to grant permission for your app to access private user data.

3. Wait for the user to invoke the task or action in your app that requires access to specific private user data. At that time, your app can request the runtime permission that is required for accessing that data.

4. Check whether the user has already granted

   runtime permission your app requires. If so, your app can access the private user data. If not, continue to the next step.

   You must check whether you have a permission every time you perform an operation that requires that permission.

5. Check whether your app should show a rationale to the user, explaining why your app needs the user to grant a particular runtime permission. If the system determines that your app shouldn't show a rationale, continue to the next step directly, without showing a UI element.

   If the system determines that your app should show a rationale, however, present the rationale to the user in a UI element. In this rationale, clearly explain what data your app is trying to access and what benefits the app can provide to the user if they grant the runtime permission. After the user acknowledges the rationale, continue to the next step.

6. Request the runtime permission your app requires to access the private user data. The system displays a runtime permission prompt, such as the one shown on the permissions overview page.

7. Check the user's response---whether they chose to grant or deny the runtime permission.

8. If the user granted the permission to your app, you can access the private user data. If the user denied the permission instead, gracefully degrade your app experience so that it provides functionality to the user without the information that's protected by that permission.

Figure 1 illustrates the workflow and set of decisions associated with this process: Image: A flowchart illustrating the decision process for requesting runtime permissions, starting with an app action, checking if permission is granted, checking if rationale is needed, requesting permission, and handling the user's response. Figure 1. Diagram that shows the workflow for declaring and requesting runtime permissions on Android.

Determine whether your app was already granted the permission

To check whether the user already granted your app a particular permission, pass that permission into the ContextCompat.checkSelfPermission() method. This method returns either PERMISSION_GRANTED or PERMISSION_DENIED, depending on whether your app has the permission.

Explain why your app needs the permission

The permissions dialog shown by the system when you call requestPermissions() says what permission your app wants, but doesn't say why. In some cases, the user might find that puzzling. It is a good idea to explain to the user why your app wants the permissions before you call requestPermissions().

Research shows that users are much more comfortable with permissions requests if they know why the app needs them, such as whether the permission is needed to support a core feature of the app or for advertising. As a result, if you are only using a fraction of the API calls that fall under a permission group, explicitly list which of those permissions you are using and why. For example, if you are only using coarse location, let the user know this in your app description or in help articles about your app.

Under certain conditions, it is also helpful to let users know about sensitive data access in real time. For example, if you are accessing the camera or microphone, consider letting the user know by using a notification icon somewhere in your app, or in the notification tray (if the application is running in the background), so it doesn't seem like you are collecting data surreptitiously.

[!NOTE] Note: Starting in Android 12 (API level 31), privacy indicators notify the user whenever applications access the microphone or camera.

If you need to request a permission for a feature to work, but the reason is not clear to the user, find a way to explain why you need sensitive permissions.

If the ContextCompat.checkSelfPermission() method returns PERMISSION_DENIED, call shouldShowRequestPermissionRationale(). If this method returns true, show an educational UI to the user. In this UI, describe why the feature that the user wants to enable needs a particular permission.

Additionally, if your app requests a permission related to location, microphone, or camera, consider explaining why your app needs access to this information.

Request permissions

After the user views an educational UI, or the return value of shouldShowRequestPermissionRationale() indicates that you don't need to show an educational UI, request the permission. Users see a system permission dialog, where they can choose whether to grant a particular permission to your app.

To do this, use the RequestPermission contract, included in an AndroidX library, where you allow the system to manage the permission request code for you. Because using the RequestPermission contract simplifies your logic, it is the recommended solution when possible. However, if needed you can also manage a request code yourself as part of the permission request and include this request code in your permission callback logic.

Allow the system to manage the permission request code

To allow the system to manage the request code that is associated with a permissions request, add dependencies on the following libraries in your module's build.gradle file:

• androidx.activity, version 1.2.0 or later

• androidx.fragment, version 1.3.0 or later

You can then use one of the following classes:

• To request a single permission, use RequestPermission.

• To request multiple permissions at the same time, use RequestMultiplePermissions.

The following steps show how to use the RequestPermission contract. The process is nearly the same for the RequestMultiplePermissions contract.

1. In your activity or fragment's initialization logic, pass in an implementation of ActivityResultCallback into a call to registerForActivityResult(). The ActivityResultCallback defines how your app handles the user's response to the permission request.

   Keep a reference to the return value of registerForActivityResult(), which is of type ActivityResultLauncher.

2. To display the system permissions dialog when necessary, call the launch() method on the instance of ActivityResultLauncher that you saved in the previous step.

   After launch() is called, the system permissions dialog appears. When the user makes a choice, the system asynchronously invokes your implementation of ActivityResultCallback, which you defined in the previous step. Note: Your app cannot customize the dialog that appears when you call launch(). To provide more information or context to the user, change your app's UI so that it's easier for users to understand why a feature in your app needs a particular permission. For example, you might change the text in the button that enables the feature.

   Also, the text in the system permission dialog references the permission group associated with the permission that you requested. This permission grouping is designed for system ease-of-use, and your app shouldn't rely on permissions being within or outside of a specific permission group.

The following code snippet shows how to handle the permissions response:

Kotlin

when {
    ContextCompat.checkSelfPermission(
            CONTEXT,
            Manifest.permission.REQUESTED_PERMISSION
            ) == PackageManager.PERMISSION_GRANTED -> {
        // You can use the API that requires the permission.
        performAction(...)
    }
    ActivityCompat.shouldShowRequestPermissionRationale(
            this, Manifest.permission.REQUESTED_PERMISSION) -> {
        // In an educational UI, explain to the user why your app requires this
        // permission for a specific feature to behave as expected, and what
        // features are disabled if it's declined. In this UI, include a
        // "cancel" or "no thanks" button that lets the user continue
        // using your app without granting the permission.
        showInContextUI(...)
    }
    else -> {
        // You can directly ask for the permission.
        requestPermissions(CONTEXT,
                arrayOf(Manifest.permission.REQUESTED_PERMISSION),
                REQUEST_CODE)
    }
}

Java

if (ContextCompat.checkSelfPermission(
        CONTEXT, Manifest.permission.REQUESTED_PERMISSION) ==
        PackageManager.PERMISSION_GRANTED) {
    // You can use the API that requires the permission.
    performAction(...);
} else if (ActivityCompat.shouldShowRequestPermissionRationale(
        this, Manifest.permission.REQUESTED_PERMISSION)) {
    // In an educational UI, explain to the user why your app requires this
    // permission for a specific feature to behave as expected, and what
    // features are disabled if it's declined. In this UI, include a
    // "cancel" or "no thanks" button that lets the user continue
    // using your app without granting the permission.
    showInContextUI(...);
} else {
    // You can directly ask for the permission.
    requestPermissions(CONTEXT,
            new String[] { Manifest.permission.REQUESTED_PERMISSION },
            REQUEST_CODE);
}

And this code snippet demonstrates the recommended process to check for a permission and to request a permission from the user when necessary:

Kotlin

when {
    ContextCompat.checkSelfPermission(
            CONTEXT,
            Manifest.permission.REQUESTED_PERMISSION
            ) == PackageManager.PERMISSION_GRANTED -> {
        // You can use the API that requires the permission.
    }
    ActivityCompat.shouldShowRequestPermissionRationale(
            this, Manifest.permission.REQUESTED_PERMISSION) -> {
        // In an educational UI, explain to the user why your app requires this
        // permission for a specific feature to behave as expected, and what
        // features are disabled if it's declined. In this UI, include a
        // "cancel" or "no thanks" button that lets the user continue
        // using your app without granting the permission.
        showInContextUI(...)
    }
    else -> {
        // You can directly ask for the permission.
        // The registered ActivityResultCallback gets the result of this request.
        requestPermissionLauncher.launch(
                Manifest.permission.REQUESTED_PERMISSION)
    }
}

Java

if (ContextCompat.checkSelfPermission(
        CONTEXT, Manifest.permission.REQUESTED_PERMISSION) ==
        PackageManager.PERMISSION_GRANTED) {
    // You can use the API that requires the permission.
    performAction(...);
} else if (ActivityCompat.shouldShowRequestPermissionRationale(
        this, Manifest.permission.REQUESTED_PERMISSION)) {
    // In an educational UI, explain to the user why your app requires this
    // permission for a specific feature to behave as expected, and what
    // features are disabled if it's declined. In this UI, include a
    // "cancel" or "no thanks" button that lets the user continue
    // using your app without granting the permission.
    showInContextUI(...);
} else {
    // You can directly ask for the permission.
    // The registered ActivityResultCallback gets the result of this request.
    requestPermissionLauncher.launch(
            Manifest.permission.REQUESTED_PERMISSION);
}

Manage the permission request code yourself

As an alternative to allowing the system to manage the permission request code, you can manage the permission request code yourself. To do so, include the request code in a call to requestPermissions().

[!NOTE] Note: Your app cannot customize the dialog that appears when you call requestPermissions(). The text in the system permission dialog references a permission group, but this permission grouping is designed for system ease-of-use. Your app must not rely on permissions being within or outside of a specific permission group.

The following code snippet demonstrates how to request a permission using a request code:

Kotlin

when {
    ContextCompat.checkSelfPermission(
            CONTEXT,
            Manifest.permission.REQUESTED_PERMISSION
            ) == PackageManager.PERMISSION_GRANTED -> {
        // You can use the API that requires the permission.
        performAction(...)
    }
    ActivityCompat.shouldShowRequestPermissionRationale(
            this, Manifest.permission.REQUESTED_PERMISSION) -> {
        // In an educational UI, explain to the user why your app requires this
        // permission for a specific feature to behave as expected, and what
        // features are disabled if it's declined. In this UI, include a
        // "cancel" or "no thanks" button that lets the user continue
        // using your app without granting the permission.
        showInContextUI(...)
    }
    else -> {
        // You can directly ask for the permission.
        requestPermissions(CONTEXT,
                arrayOf(Manifest.permission.REQUESTED_PERMISSION),
                REQUEST_CODE)
    }
}

Java

if (ContextCompat.checkSelfPermission(
        CONTEXT, Manifest.permission.REQUESTED_PERMISSION) ==
        PackageManager.PERMISSION_GRANTED) {
    // You can use the API that requires the permission.
    performAction(...);
} else if (ActivityCompat.shouldShowRequestPermissionRationale(
        this, Manifest.permission.REQUESTED_PERMISSION)) {
    // In an educational UI, explain to the user why your app requires this
    // permission for a specific feature to behave as expected, and what
    // features are disabled if it's declined. In this UI, include a
    // "cancel" or "no thanks" button that lets the user continue
    // using your app without granting the permission.
    showInContextUI(...);
} else {
    // You can directly ask for the permission.
    requestPermissions(CONTEXT,
            new String[] { Manifest.permission.REQUESTED_PERMISSION },
            REQUEST_CODE);
}

After the user responds to the system permissions dialog, the system then invokes your app's implementation of onRequestPermissionsResult(). The system passes in the user response to the permission dialog, as well as the request code that you defined, as shown in the following code snippet:

Kotlin

override fun onRequestPermissionsResult(requestCode: Int,
        permissions: Array<String>, grantResults: IntArray) {
    when (requestCode) {
        PERMISSION_REQUEST_CODE -> {
            // If request is cancelled, the result arrays are empty.
            if ((grantResults.isNotEmpty() &&
                    grantResults[0] == PackageManager.PERMISSION_GRANTED)) {
                // Permission is granted. Continue the action or workflow
                // in your app.
            } else {
                // Explain to the user that the feature is unavailable because
                // the feature requires a permission that the user has denied.
                // At the same time, respect the user's decision. Don't link to
                // system settings in an effort to convince the user to change
                // their decision.
            }
            return
        }

        // Add other 'when' lines to check for other
        // permissions this app might request.
        else -> {
            // Ignore all other requests.
        }
    }
}

Java

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions,
        int[] grantResults) {
    switch (requestCode) {
        case PERMISSION_REQUEST_CODE:
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0 &&
                    grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // Permission is granted. Continue the action or workflow
                // in your app.
            }  else {
                // Explain to the user that the feature is unavailable because
                // the feature requires a permission that the user has denied.
                // At the same time, respect the user's decision. Don't link to
                // system settings in an effort to convince the user to change
                // their decision.
            }
            return;
        }
        // Other 'case' lines to check for other
        // permissions this app might request.
    }
}

Request location permissions

When you request location permissions, follow the same best practices as for any other runtime permission. One important difference when it comes to location permissions is that the system includes multiple permissions related to location. Which permissions you request, and how you request them, depend on the location requirements for your app's use case.

Foreground location

If your app contains a feature that shares or receives location information only once, or for a defined amount of time, then that feature requires foreground location access. Some examples include the following:

• Within a navigation app, a feature lets users get turn-by-turn directions.

• Within a messaging app, a feature lets users share their current location with another user.

The system considers your app to be using foreground location if a feature of your app accesses the device's current location in one of the following situations:

• An activity that belongs to your app is visible.

• Your app is running a foreground service. When a foreground service is running, the system raises user awareness by showing a persistent notification. Your app retains access when it is placed in the background, such as when the user presses the Home button on their device or turns their device's display off.

  On Android 10 (API level 29) and higher, you must declare a foreground service type of location, as shown in the following code snippet. On earlier versions of Android, we recommend that you declare this foreground service type.

  Copy

  <!-- Recommended for Android 9 (API level 28) and lower. -->
  <!-- Required for Android 10 (API level 29) and higher. -->
  <service
      android:name="MyNavigationService"
      android:foregroundServiceType="location" ... >
      <!-- Any inner elements go here. -->
  </service>

You declare a need for foreground location when your app requests either the ACCESS_COARSE_LOCATION permission or the ACCESS_FINE_LOCATION permission, as shown in the following snippet:

<manifest ... >
  <!-- Include this permission any time your app needs location information. -->
  <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

  <!-- Include only if your app benefits from precise location access. -->
  <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
</manifest>

Background location

An app requires background location access if a feature within the app constantly shares location with other users or uses the Geofencing API. Several examples include the following:

• Within a family location sharing app, a feature lets users continuously share location with family members.

• Within an IoT app, a feature lets users configure their home devices such that they turn off when the user leaves their home and turn back on when the user returns home.

The system considers your app to be using background location if it accesses the device's current location in any situation other than the ones described in the foreground location section. The background location accuracy is the same as the foreground location accuracy, which depends on the location permissions that your app declares.

On Android 10 (API level 29) and higher, you must declare the ACCESS_BACKGROUND_LOCATION permission in your app's manifest to request background location access at runtime. On earlier versions of Android, when your app receives foreground location access, it automatically receives background location access as well.

<manifest ... >
  <!-- Required only when requesting background location access on
       Android 10 (API level 29) and higher. -->
  <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
</manifest>

[!NOTE] Note: The Google Play Store has a location policy concerning device location, restricting background location access to apps that need it for their core functionality and meet related policy requirements.

Handle permission denial

If the user denies a permission request, your app must help them understand the implications of denying the permission. In particular, your app must make users aware of the features that don't work because of the missing permission. When you do so, keep the following best practices in mind:

• Minimize functionality loss. Users should be able to access the app to whatever extent is possible without the requested permissions. If functionality works at least to some extent with the data available, even if it is degraded compared to what would have been possible with the permission, keeping it on is the best option.

• Guide the user's attention. Highlight a specific part of your app's UI where there is limited functionality because your app doesn't have the necessary permission. Examples of what you can do include the following:

  • Show a message where the feature's results or data would have appeared.

  • Display a different button that contains an error icon and color.

• Be specific. Don't display a generic message. Instead, make clear which features are unavailable because your app doesn't have the necessary permission.

• Don't block the user interface. In other words, don't display a full-screen warning message that prevents users from continuing to use your app at all.

• Accept the user's preference: While it is okay to communicate to users how their functionality is being impacted by lack of access to the requested permissions, they should not feel pressured to change their mind. Letting a user know that they aren't getting full feature access when it is appropriate (such as when attempting to use a part of the app blocked without the permission) is important, but persistent nagging to reconsider is not respectful of their choice.

Following these guidelines can help ensure that users feel empowered to manage access to their private data in a way that aligns with their values. Failing to gracefully accept highly visible user privacy decisions damages the trust and reputation not only of your app, but of the ecosystem as a whole.

[!TIP] Tip: We recommend that your app encourages the best user experience possible, even after permission denials. For example, if microphone access is denied, you must still promote full usability of text functionality.

Additionally, if the user taps Deny for a specific permission more than once during your app's lifetime of installation on a device, the user will no longer see the system permissions dialog if your app requests that permission again. The user's action implies "don't ask again," and is considered a permanent denial. It is very important to only prompt users for permissions when they need access to a specific feature; otherwise, you might inadvertently lose the ability to re-request permissions. In certain situations, the permission might be denied automatically, without the user taking any action. (A permission might be granted automatically as well.) It is important to not assume anything about automatic behavior. Each time your app needs to access functionality that requires a permission, check that your app is still granted that permission. To provide the best user experience when asking for app permissions, also see App permissions best practices.

Inspect denial status when testing and debugging

To identify whether an app has been permanently denied permissions (for debugging and testing purposes), use the following command:

adb shell dumpsys package PACKAGE_NAME

Where <var translate="no">PACKAGE_NAME</var> is the name of the package to inspect.

The output of the command contains sections that look like this:

...
runtime permissions:
  android.permission.POST_NOTIFICATIONS: granted=false, flags=[ USER_SENSITIVE_WHEN_GRANTED|USER_SENSITIVE_WHEN_DENIED]
  android.permission.ACCESS_FINE_LOCATION: granted=false, flags=[ USER_SET|USER_FIXED|USER_SENSITIVE_WHEN_GRANTED|USER_SENSITIVE_WHEN_DENIED]
  android.permission.BLUETOOTH_CONNECT: granted=false, flags=[ USER_SENSITIVE_WHEN_GRANTED|USER_SENSITIVE_WHEN_DENIED]
...

Permissions that have been denied once by the user are flagged by USER_SET. Permissions that have been denied permanently by selecting Deny twice are flagged by USER_FIXED.

To make sure that testers see the request dialog during testing, reset these flags when you're done debugging your app. To do this, use the command:

adb shell pm clear-permission-flags PACKAGE_NAME PERMISSION_NAME user-set user-fixed

<var translate="no">PERMISSION_NAME</var> is the name of the permission you want to reset.

PERMISSION_NAME is the name of the permission you want to reset.

To view a complete list of Android app permissions, visit the permissions API reference page.

One-time permissions

Image: The option called 'Only this time' is the second of three buttons in the dialog. Figure 2. System dialog that appears when an app requests a one-time permission.

Starting in Android 11 (API level 30), whenever your app requests a permission related to location, microphone, or camera, the user-facing permissions dialog contains an option called Only this time , as shown in figure 2. If the user selects this option in the dialog, your app is granted a temporary one-time permission.

Your app can then access the related data for a period of time that depends on your app's behavior and the user's actions:

• While your app's activity is visible, your app can access the data.

• If the user sends your app to the background, your app can continue to access the data for a short period of time.

• If you launch a foreground service while the activity is visible, and the user then moves your app to the background, your app can continue to access the data until the foreground service stops.

App process terminates when permission revoked

If the user revokes the one-time permission, such as in system settings, your app cannot access the data, regardless of whether you launched a foreground service. As with any permission, if the user revokes your app's one-time permission, your app's process terminates.

When the user next opens your app and a feature in your app requests access to location, microphone, or camera, the user is prompted for the permission again.

[!NOTE] Note: If your app already follows best practices when it requests runtime permissions, you don't need to add or change any logic in your app to support one-time permissions.

Reset unused permissions

Android provides several ways to reset unused runtime permissions to their default, denied state:

• An API where you can proactively remove your app's access to an unused runtime permission.

• A system mechanism that automatically resets the permissions of unused apps.

Remove app access

On Android 13 (API level 33) and higher, you can remove your app's access to runtime permissions that your app no longer requires. When you update your app, perform this step so that users are more likely to understand why your app continues to request specific permissions. This knowledge helps build user trust in your app.

To remove access to a runtime permission, pass the name of that permission into revokeSelfPermissionOnKill(). To remove access to a group of runtime permissions at the same time, pass a collection of permission names into revokeSelfPermissionsOnKill(). The permission removal process happens asynchronously and kills all processes associated with your app's UID.

[!NOTE] Note: For system settings to show that your app doesn't access data in a particular permission group, you must remove access to all permissions in that permission group. In this case, it can be helpful to call revokeSelfPermissionsOnKill() and pass in multiple permissions within the permission group.

For the system to remove your app's access to the permissions, all processes tied to your app must be killed. When you call the API, the system determines when it is safe to kill these processes. Usually, the system waits until your app spends an extended period of time running in the background instead of the foreground.

To inform the user that your app no longer requires access to specific runtime permissions, show a dialog the next time the user launches your app. This dialog can include the list of permissions.

Auto-reset permissions of unused apps

If your app targets Android 11 (API level 30) or higher and is not used for a few months, the system protects user data by automatically resetting the sensitive runtime permissions that the user had granted your app. Learn more in the guide about app hibernation.

Request to become the default handler if necessary

Some apps depend on access to sensitive user information related to call logs and SMS messages. If you want to request the permissions specific to call logs and SMS messages and publish your app to the Play Store, you must prompt the user to set your app as the default handler for a core system function before requesting these runtime permissions.

For more information on default handlers, including guidance on showing a default handler prompt to users, see the guide about permissions used only in default handlers.

Grant all runtime permissions for testing purposes

To grant all runtime permissions automatically when you install an app on an emulator or test device, use the -g option for the adb shell install command, as demonstrated in the following code snippet:

adb shell install -g PATH_TO_APK_FILE

Additional resources

For additional information about permissions, read these articles:

• Permissions overview

• App permissions best practices

To learn more about requesting permissions, review the permissions samples.

You can also complete this codelab that demonstrates privacy best practices.