Publishing Flutter Firebase App to Play Store

5 min readNov 10, 2020

In this tutorial, we will be seeing how we can publish flutter applications with firebase to play store. Even if you are not using firebase you can follow along as there are only a few extra steps to configure firebase.

To follow along with this you will need a working flutter application, firebase project for the app and a google developer account.

Preparing the app for release

Update app manifest

Review your AndroidManifest.xml located in app dir/android/app/src/main

Edit android:label under application to reflect the final app name.

Change the launcher icon. Appicon.co is a good place to generate icons.

You can refer here to learn more about setting up the launcher icon.

Add required permissions for your app above application tag.

Changing the package name

If you have package name other than com.example.* skip this step.

By default, your app might have a package name like com.example.* which won’t be accepted by the play store.

Refer here to learn how to change the package name.

Updating build.gradle file

Here we are going to change the build.gradle file located in app dir/android/app

Add the code given below above android block.

def keystoreProperties = new Properties()
   def keystorePropertiesFile = rootProject.file('key.properties')
   if (keystorePropertiesFile.exists()) {
       keystoreProperties.load(new  FileInputStream(keystorePropertiesFile))
   }android {
...
}

2. Under the android block change the compileSdkVersion and targetSdkVersion to 29 or 30, else play store won’t accept it due to security reasons.

3. Under the android block find buildTypes block and change the line signingConfig signingConfigs.debug to signingConfig signingConfigs.release.

4. Under the android block add these lines:

signingConfigs {
release {
keyAlias keystoreProperties['keyAlias']
keyPassword keystoreProperties['keyPassword']
storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
storePassword keystoreProperties['storePassword']
}
}

After doing all the above changes your build.gradle should look similar to this (Start referring from line 27) :

Create a Keystore

If you have an existing Keystore, skip to the next step.

After executing the below command it will ask a number of questions. Fill all of those or it will give a warning that certificate is not trusted or something similar.

Default keytool password: android

On Mac/Linux, use the following command:

keytool -genkey -v -keystore ~/key.jks -keyalg RSA -keysize 2048 -validity 10000 -alias key

On Windows, use the following command:

keytool -genkey -v -keystore c:\Users\USER_NAME\key.jks -storetype JKS -keyalg RSA -keysize 2048 -validity 10000 -alias key

The above command will generate a key.jks file in your home directory. If you get any errors it may be caused by the absence of keytool command in your path. In that case use flutter doctor -v and get the path under Java binary at.

Keep this file handy, we will need it soon.

Reference the Keystore from the app

Create a file named app dir/android/key.properties that contains a reference to your Keystore:

storePassword=<password from previous step>
keyPassword=<password from previous step>
keyAlias=key
storeFile=<location of the key store file, such as /Users/<user name>/key.jks>

With this we are done with the app side of things. Now lets dive into Firebase configurations.

Preparing Firebase for release

This is how your firebase project settings might be looking with debug keys.

To make it work once your app is in play store we need to add release keys from the key.jks and app signing key from Google play console.

Getting the release keys

Go to the directory where you have stored your key.jks file. Execute the following command

keytool -list -v -keystore key.jks

From here copy the SHA1 and SHA256 and add to your Firebase project settings.

Getting app signing key

Login to your Google play console.
Go to Create app and fill the required information.
Go to Setup>App signing.
Hit the Create release button.
On the new screen see top right corner Create new release.
Under App signing by Google Play hit continue.
Again go to Setup>App signing. Get the SHA-1 key under the App signing key certificate section.

After completing all the above steps your firebase project settings should have at least 3 SHA-1 keys (degub, release & app signing).

We are almost there…

Now download the updated google-services.json and replace the older one.
Execute flutter clean in your project root directory.
Create a release app bundle using the command below. Make sure you are in your flutter project root directory.

flutter build appbundle --target-platform android-arm,android-arm64,android-x64

After executing the above command it will provide you with the complete path to the generated file. Copy that file to somewhere else where it is more accessible.

The Finale

Go to your app dashboard and fill up the boring questionnaire.
Under Grow tab, go to Store presence>Main store listing and provide some more information.
Go to Production, under Countries/regions select where you want your app to be accessible.
Finally, Create new release upload your *.aab file.