---
id: signed-apk-android
title: Generating Signed APK
layout: docs
category: Guides (Android)
permalink: docs/signed-apk-android.html
next: activityindicatorios
---

To distribute your Android application via [Google Play store](https://play.google.com/store), you'll need to generate a signed release APK. The [Signing Your Applications](https://developer.android.com/tools/publishing/app-signing.html) page on Android Developers documentation describes the topic in detail. This guide covers the process in brief, as well as lists the steps required to packaging the JavaScript bundle.

### Generating a signing key

You can generate a private signing key using `keytool`.

    $ keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -keysize 2048 -validity 10000

This command prompts you for passwords for the keystore and key, and to provide the Distinguished Name fields for your key. It then generates the keystore as a file called `my-release-key.keystore`.

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.

_Note: Remember to keep your keystore file private and never commit it to version control._

### Setting up gradle variables

1. Place the `my-release-key.keystore` file under the `android/app` directory in your project folder.
2. Edit the file `~/.gradle/gradle.properties` and add the following (replace `*****` with the correct keystore password, alias and key password),

```
MYAPP_RELEASE_STORE_FILE=my-release-key.keystore
MYAPP_RELEASE_STORE_PASSWORD=*****
MYAPP_RELEASE_KEY_ALIAS=*****
MYAPP_RELEASE_KEY_PASSWORD=*****
```

These are going to be global gradle variables, which we can later use in our gradle config to sign our app.

_Note: Once you publish the app on the Play Store, you will need to republish your app under a different package name (loosing all downloads and ratings) if you want to change the signing key at any point. So backup your keystore and don't forget the passwords._

### Adding signing config to your app's gradle config

Edit the file `android/app/build.gradle` in your project folder and add the signing config,

```
...
android {
    ...
    defaultConfig { ... }
    signingConfigs {
        release {
            storeFile file(MYAPP_RELEASE_STORE_FILE)
            storePassword MYAPP_RELEASE_STORE_PASSWORD
            keyAlias MYAPP_RELEASE_KEY_ALIAS
            keyPassword MYAPP_RELEASE_KEY_PASSWORD
        }
    }
    buildTypes {
        release {
            ...
            signingConfig signingConfigs.release
        }
    }
}
...
```

### Generating the APK

1. Start the packager by running `npm start` in your project folder
2. In your project folder, run the following in a Terminal,

```sh
$ mkdir -p android/app/src/main/assets
$ curl "http://localhost:8081/index.android.bundle?platform=android&dev=false&minify=true" -o "android/app/src/main/assets/index.android.bundle"
$ cd android && ./gradlew assembleRelease
```

The generated APK can be found under `android/app/build/outputs/apk/app-release.apk`, and is ready to be distributed.