Testing Android App Bundles: A Complete Step-by-Step Guide

As a mobile app testing expert with over 10 years of experience across 3,500+ real devices, I often get questions about properly testing Android App Bundles.

In this comprehensive guide, I‘ll provide detailed, step-by-step instructions for creating, testing, and publishing app bundles to ensure optimal delivery. Whether you‘re new to bundle testing or an experienced Android developer, this article will equip you with the key information you need.

What Exactly Are App Bundles?

First, a quick background on what bundles are and how they benefit apps.

An Android App Bundle is a publishing format that defers APK generation and signing to Google Play. The developer uploads a single bundle, and Google Play dynamically delivers optimized APKs to users based on their device configuration.

The main benefits this offers are:

• Smaller app sizes – app bundles allow up to 35% reduction in size
• Easier modular development
• Streamlined delivery and updates

By leveraging app bundles, you can provide a lighter, more optimized experience for end users.

Step 1: Creating an App Bundle in Android Studio

The first step is generating a signed app bundle for release. Here I‘ll walk through this process within Android Studio:

1. In Android Studio, go to Build > Generate Signed Bundle
2. Select Android App Bundle and click Next
3. Enter keystore info if creating a new one, or locate existing keystore
4. For build variants, choose release mode
5. Click finish to generate the bundle

You‘ll find the .aab file in app/build/outputs/bundle/release.

Make sure to configure the app-level build.gradle with the proper bundle and signing configs as well:

android {
    // Configures release builds to use app bundles
    bundle {
        language {
            // Provides splits based on language 
            enableSplit = true
        }
        density {
            // Provides splits based on screen density
            enableSplit = true
        }
    }

    signingConfigs {
        release {
            keyAlias ‘myReleaseKey‘
            keyPassword ‘password‘ 
            storeFile file(‘my_key.keystore‘) 
            storePassword ‘password‘
        }
    }

    buildTypes {
        release {
            // Signs release bundles with release config
            signingConfig signingConfigs.release
        }
    }
}

This ensures optimized splits based on language, density, and other device characteristics.

Step 2: Testing App Bundles Locally

Next we‘ll use the command line tool bundletool to validate how the bundle tailors resource delivery for different configurations.

First, build a universal APK set archive (.apks) containing all configs:

java -jar bundletool-all.jar build-apks --bundle="app.aab" --output="app.apks"  

The output archive contains optimized APK splits for each configuration your app supports.

You can also install these directly to a connected device with:

java -jar bundletool-all.jar install-apks --apks=app.apks

To test what a user would actually receive based on their device specs, build a specific APK set:

bundletool build-apks --connected-device --bundle="app.aab" --output="pixel5-apks" 

Use thisflows to validate the delivery process end-to-end before publishing.

Step 3: Real Device Testing

While local validation is useful, I always recommend testing bundles on real devices as well. Cloud platforms like BrowserStack give you instant access to 3000+ real Android and iOS devices – exactly what end users will experience.

Some key advantages:

• Test on different Android versions and manufacturers
• Validate localization and right-to-left text
• Confirm optimizations for various chipsets
• Run automation test suites across devices

Real device cloud testing improves test coverage and confidence before public launch.

Step 4: Publishing and Monitoring App Bundles

Once you‘ve verified expected behavior, publish your tested release bundle to Google Play.

In the Play Console, closely track key metrics after launch:

• Device compatibility – ensure all intended devices are supported
• Adoption rates – how quickly are users getting upgrades?
• Crash rates – are any device configs seeing higher crashes?

Address any issues immediately by iterating on your app bundle. For example, you can enable or disable splits for specific device dims if needed.

Conclusion

I hope this guide gives you a comprehensive understanding of successfully testing and releasing Android App Bundles. Please reach out if you have any other questions! I‘m always happy to help explain best practices based on my decade of mobile app testing experience.

By following these steps and leveraging real device cloud testing, you can ensure reliable, optimized delivery of your app to users worldwide.