Generating an upload key
You can generate a private signing key using
keytool. On Windows
keytool must be run from
This command prompts you for passwords for the keystore and key and for the Distinguished Name fields for your key. It then generates the keystore as a file called
The keystore contains a single key, valid for 10000 days. The alias is a name that you will use later when signing your app, so remember to take note of the alias.
On Mac, if you're not sure where your JDK bin folder is, then perform the following command to find it:
It will output the directory of the JDK, which will look something like this:
Navigate to that directory by using the command
$ cd /your/jdk/path and use the keytool command with sudo permission as shown below.
Note: Remember to keep the keystore file private. In case you've lost upload key or it's been compromised you should follow these instructions.
Setting up Gradle variables
- Place the
my-upload-key.keystorefile under the
android/appdirectory in your project folder.
- Edit the file
android/gradle.properties, and add the following (replace
*****with the correct keystore password, alias and key password),
These are going to be global Gradle variables, which we can later use in our Gradle config to sign our app.
Note about security: If you are not keen on storing your passwords in plaintext, and you are running OSX, you can also store your credentials in the Keychain Access app. Then you can skip the two last rows in
Adding signing config to your app's Gradle config
The last configuration step that needs to be done is to setup release builds to be signed using upload key. Edit the file
android/app/build.gradle in your project folder, and add the signing config,
Generating the release APK
Run the following in a terminal:
android/app/build.gradle to see how you can update it to reflect these changes.
Note: Make sure gradle.properties does not include org.gradle.configureondemand=true as that will make the release build skip bundling JS and assets into the app binary.
The generated AAB can be found under
android/app/build/outputs/bundle/release/app.aab, and is ready to be uploaded to Google Play.
Note: In order for Google Play to accept AAB format the App Signing by Google Play needs to be configured for your application on the Google Play Console. If you are updating an existing app that doesn't use App Signing by Google Play, please check our migration section to learn how to perform that configuration change.
Testing the release build of your app
Before uploading the release build to the Play Store, make sure you test it thoroughly. First uninstall any previous version of the app you already have installed. Install it on the device using:
--variant=release is only available if you've set up signing as described above.
Publishing to other stores
By default, the generated APK has the native code for both x86 and ARMv7a CPU architectures. This makes it easier to share APKs that run on almost all Android devices. However, this has the downside that there will be some unused native code on any device, leading to unnecessarily bigger APKs.
You can create an APK for each CPU by changing the following line in android/app/build.gradle:
Upload both these files to markets which support device targeting, such as Google Play and Amazon AppStore, and the users will automatically get the appropriate APK. If you want to upload to other markets, such as APKFiles, which do not support multiple APKs for a single app, change the following line as well to create the default universal APK with binaries for both CPUs.
Enabling Proguard to reduce the size of the APK (optional)
Proguard is a tool that can slightly reduce the size of the APK. It does this by stripping parts of the React Native Java bytecode (and its dependencies) that your app is not using.
IMPORTANT: Make sure to thoroughly test your app if you've enabled Proguard. Proguard often requires configuration specific to each native library you're using. See
To enable Proguard, edit
Migrating old Android React Native apps to use App Signing by Google Play
If you are migrating from previous version of React Native chances are your app does not use App Signing by Google Play feature. We recommend you enable that in order to take advantage from things like automatic app splitting. In order to migrate from the old way of signing you need to start by generating new upload key and then replacing release signing config in
android/app/build.gradle to use the upload key instead of the release one (see section about adding signing config to gradle). Once that's done you should follow the instructions from Google Play Help website in order to send your original release key to Google Play.