Permission requests protect sensitive information available from a device and should only be used when access to information is necessary for the functioning of your app. This document provides tips on ways you might be able to achieve the same (or better) functionality without requiring access to such information; it is not an exhaustive discussion of how permissions work in the Android operating system.
Permissions in Android 6.0+
In Android 6.0 (API level 23) and higher, apps can request permissions from the user at runtime, rather than prior to installation. This allows apps to request permissions when the app actually requires the services or data protected by the services. While this doesn't (necessarily) change overall app behavior, it does create a few changes relevant to the way sensitive user data is handled:
Increased situational context
Users are prompted at runtime, in the context of your app, for permission to access the functionality covered by those permission groups. Users are more sensitive to the context in which the permission is requested, and if there’s a mismatch between what you are requesting and the purpose of your app, it's even more important to provide detailed explanation to the user as to why you’re requesting the permission. Whenever possible, you should provide an explanation of your request both at the time of the request and in a follow-up dialog if the user denies the request.
To increase the likelihood of a permission request being accepted, only prompt when a specific feature is required. For instance, only prompt for microphone access when a user clicks on the microphone button. Users are more likely to allow a permission that they are expecting.
Greater flexibility in granting permissions
Users can deny access to individual permissions at the time they’re requested and in settings, but they may still be surprised when functionality is broken as a result. It’s a good idea to monitor how many users are denying permissions (e.g. using Google Analytics) so that you can either refactor your app to avoid depending on that permission or provide a better explanation of why you need the permission for your app to work properly. You should also make sure that your app handles exceptions when users deny permission requests or toggle off permissions in settings.
Increased transactional burden
Users are asked to grant access for permission groups individually and not as a set. This makes it extremely important to minimize the number of permissions you’re requesting. This increases the user-burden for granting permissions and therefore increases the probability that at least one of the requests will be denied.
Permissions that require becoming a default handler
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 on permissions used only in default handlers.
Know the libraries you're working with
Sometimes permissions are required by the libraries you use in your app. For
example, ads and analytics libraries may require access to the
LOCATION permissions group to implement the required
functionality. But from the user's point of view, the permission request comes
from your app, not the library.
Just as users select apps that use fewer permissions for the same
functionality, developers should review their libraries and select
third-party SDKs that aren't using unnecessary permissions. For example, if
you're using a library that provides location functionality, make sure you
aren't requesting the
FINE_LOCATION permission unless you're
using location-based targeting functionality.
Limit background access to location
When your app is running in the background, access to location should be critical to the app's core functionality and show a clear benefit to users.
Test for both permissions models
In Android 6.0 (API level 23) and higher, users grant and revoke app permissions at run time, instead of doing so when they install the app. As a result, you'll have to test your app under a wider range of conditions. Prior to Android 6.0, you could reasonably assume that if your app is running at all, it has all the permissions it declares in the app manifest. Now, the user can turn permissions on or off for any app, regardless of API level. You should test to ensure your app functions correctly across various permission scenarios.
The following tips will help you find permissions-related code problems on devices running API level 23 or higher:
- Identify your app’s current permissions and the related code paths.
- Test user flows across permission-protected services and data.
- Test with various combinations of granted or revoked permissions. For
example, a camera app might list
ACCESS_FINE_LOCATIONin its manifest. You should test the app with each of these permissions turned on and off, to make sure the app can handle all permission configurations gracefully.
- Use the adb tool to manage
permissions from the command line:
- List permissions and status by group:
$ adb shell pm list permissions -d -g
- Grant or revoke one or more permissions:
$ adb shell pm [grant|revoke] <permission-name> ...
- List permissions and status by group:
- Analyze your app for services that use permissions.
- Material Design guidelines for Android permissions
- Android Marshmallow 6.0: Asking For Permission: This video explains the Android runtime permission model and the right way to ask users for permissions.
- Explain why the app needs permissions
- Best practices for unique identifiers