Android Builds

Build and submit Android apps to Google Play Store using Capgo’s dedicated infrastructure.

What you will learn

• You will learn how to upload your app via Capgo Native build
• You will learn how to configure the credentials for Capgo Native Build

Prerequisites

• You need to have an active Google Developer account
• You need to have Android Studio installed
• Your app must be able to build successfully with Android Studio

Note

I will use the following app for the tutorial: https://github.com/Cap-go/capgo-native-build-tutorial-app

The first manual build

Before we can start thinking about building the app with Capgo, we should first set it up, and do a first Android build by hand. There are some advantages to doing a manual build first:

• You will prepare the credentials for the later Capgo build
• You will create a record on the Play Store Console

Building the app manually with Android Studio

Before we can start building the app with Capgo, we need to build the app manually with Android Studio.

1. Open Android Studio

   Run bunx cap open android to open the Android Studio project.

2. Click on Build -> Generate Signed App Bundles / APKs

3. Select Android App Bundle and click on Next

Creating a Keystore

Right now, you are missing the keystore file. This file is used to sign your app, which lets Google know that it’s you who built the app. To generate it, we will use the GUI method provided by Android Studio. There is also a way to do this with the command line, but we will not cover that in this tutorial.

1. Click on Create new

2. Fill in the Key Store path

   Caution

   This IS TO BE SAVED - it will be used later

3. Set the Key Store password

   Note

   I recommend using the same password for the Key Store and the Key Alias.

   Caution

   This IS TO BE SAVED - it will be used later

4. Fill the rest of the form

   1. Keep the Key Alias as is (key0)
   2. Fill the certificate details. I have filled it with fake details, but you should fill it with your own details.

   

5. Click on OK

1. Make sure all of the details for the keystore have been filled in correctly and click on Next

2. Select the release build variant and click on Create

3. After the build succeeds, you should see the following screen

   1. This popup indicates that the build succeeded.
   2. Click on the locate button - this will open the file explorer and you should see the build there.

4. Make sure you can see the build in the file explorer

Configuring Capgo Native Build (Android)

Requirement	Flag	Description	Required
Keystore file	--keystore <path>	Path to your .jks/.keystore file used to sign the APK/AAB.	Yes
Keystore alias	--keystore-alias <alias>	Alias name of the key inside the keystore.	Yes
Keystore key password	--keystore-key-password <password>	Password for the key. If key/store passwords match, you can provide only one.	Look at the note below
Keystore store password	--keystore-store-password <password>	Password for the keystore. If key/store passwords match, you can provide only one.	Look at the note below
Google Play service account	--play-config <path>	JSON service account file for Play Store uploads.	Yes

bunx @capgo/cli build credentials save --platform android \
  --keystore ./path/to/keystore.jks \
  --keystore-alias "your-alias" \
  --keystore-key-password "key-password" \
  --keystore-store-password "store-password" \
  --play-config ./play-store-service-account.json

Note

If key and store passwords are identical, provide only one of --keystore-key-password or --keystore-store-password.

Keystore, keystore password, keystore key password, keystore alias

If you have followed the manual build instructions, you should have the keystore already generated. If you have not followed the instructions, please follow them to generate the keystore.

Google Play service account

Generating the Google Play service account is a manual and complex process. Yet, it is required to upload your app to Google Play. Please keep in mind the following things:

• You NEED to be the owner of the Developer Account. Otherwise, you will not be able to setup the service account.
• You will need to create a new Google Cloud Project (separate from your Google Play Account)

Let’s begin.

1. Go to Google Cloud Console

2. Click on the project selector

3. If you already have a project, select it. Otherwise, create a new project:

   Note

   The screenshots below are illustrative - use a name appropriate for your project.

   1. Click on New project
   2. Name your project and click Create
   3. Ensure that you are on the right project

4. Let’s click on the search bar and search for service accounts and click on it

5. Let’s click on Create service account

6. Fill in the form for the service account and click on Done

   1. I recommend setting the name to Capgo Native Build Service Account
   2. For the Service Account ID, I recommend setting it to capgo-native-build-service-acc
   3. As for the description, you don’t have to fill it in, but I recommend filling it with Allows Capgo Native Build to build and submit the app to the Play Store

   

7. Click on the newly created service account You should now see the newly created service account in the list. Click on it.

8. Click on the Keys tab

9. Click on Add Key and Create new key

10. Click on JSON and Create

    Caution

    Clicking on Create will create a new key and it will download the JSON file to your local machine.

    You need to save the JSON file in a safe place. It WILL be used later.

11. Download the JSON file The JSON file should have been downloaded automatically. You can click on close to close the window.

Saving the credentials

You can save the credentials using the following command:

bunx @capgo/cli build credentials save --platform android \
  --keystore ./path/to/keystore.jks \
  --keystore-alias "your-alias" \
  --keystore-key-password "key-password" \
  --keystore-store-password "store-password" \
  --play-config ./play-store-service-account.json