Android apps will soon be required to adopt Android app bundles
Starting in August 2021, Google Play will require all new apps to be submitted as Android App Bundles (AABs), which offer greater efficiency than APKs, according to Google.
Application bundles are signed binaries that organize your application code and resources into modules […] The code and resources for each module are organized the same way you would find in an APK, and this makes sense because each of these modules can be generated as separate APKs. Google Play then uses the bundle app to generate the various APKs that are offered to users, such as Basic APK, Feature APKs, Setup APKs, and (for devices that do not support Split APKs ) multi-APKs.
It’s important to note that AAB will only be used by developers to submit apps to the store, while APK will remain the format used to distribute apps to users’ devices. Only they will receive personalized and optimized APKs.
According to Google, the AAB format offers a number of advantages over APKs. First, the optimization enabled by AAB makes the applications served to users 15% smaller. Additionally, AAB provides a way to customize the functionality that is efficiently delivered using Play Feature Delivery and supports dynamic delivery of large assets using Play Resource Delivery.
The play feature broadcasting offers four broadcasting modes: installation time, to provide functionality when the application is installed; on demand, which allow functionality to be requested as needed; conditional, which allows you to specify installation requirements, such as minimum operating system version, device capacity, etc. and Instant delivery, which allows you to preview the app without installing it.
Streaming Play assets supports three streaming modes: install-time, on-demand, and quick-follow. Quick Track mode will automatically download resource packs after the app is installed without waiting for the user to launch the app.
Another benefit provided by AABs is support for Google’s Secure Key Management Service, which prevents loss or compromise of credentials. This forces developers to manage Google’s signing certificates, which are required to sign APKs before distributing them to users.
AAB is supported by most building tools including Android Studio, Gradle, Bazel, Buck, and others, which will allow developers to adopt the new format almost seamlessly.
Google introduced the Android App Bundle as a mechanism for publishing apps to the Play Store in 2018. Since then, over 1 million apps have adopted it out of around 5 million apps in total. While that number might not seem like an overwhelmingly large number, Google maintains that the majority of the top 1,000 apps and games have adopted the format.