The Android App Bundle logo.
App bundles allow Google Play servers to customize an app for each user.
A mid-range phone user gets the base APK, xhdpi image assets, ARM v7 code, and English language.
Here’s a high-end phone getting the xxxhdpi asset bucket, ARM64, and a whopping three languages.
At Google I/O 2018, Google said APK configuration splits save an average of 20 percent in storage space thanks to more targeted languages, image resources, and architectures.
For more accurate app size savings, Google has shown this chart.
Google I/O 2018
Android TV will be less memory hungry in the future. Google announced that Android’s space-saving app file format, Android App Bundles (AABs), will finally be the standard on Android TV. By May 2023 – six months from now – Google requires all Android TV apps to switch to the new file format, which can reduce app storage requirements by 20 percent.
Storage for Android TV is always difficult as hardware manufacturers want to make smart TV and set top box hardware as cheap as possible, and that often means shipping with a minimal amount of storage. Google says that “in 2022, smartphones will often have a minimum storage size of 64GB, but smart TVs will only have 8GB on average.” Google itself is actually a big culprit here, with the Google Chromecast only shipping with the Google TV with 8GB of storage becomes. That’s not nearly enough, and many people are running out of storage space on the new Chromecast with just the bare minimum of content apps installed. There are 10,000 Android TV apps, some reaching over 10GB, but most Android TV users cannot install them.
Android app bundles aren’t a panacea for poorly designed devices with insufficient storage space, but every little bit helps. Android App Bundles were announced in 2018 with Android 9 to save device memory by splitting an app into modules instead of one big monolithic APK (the old Android app format) with all sorts of data. Android apps support a ton of different languages, screen resolutions, and CPU architectures, but each individual device only needs to select a few of these options in order to work. Android App Bundles integrate with the Play Store to create a dynamic delivery system for each module. Your phone will tell the Play Store what modules it needs, and Google’s servers will put together an appropriate package and send it to your device. It’s even possible for developers to move some lesser-used app features into a bundle that can be quickly downloaded when needed.
App bundles basically shift much of the responsibility for app packaging to the cloud, namely Google’s cloud, resulting in quite a dependency on Google. Developers must upload their app signing keys and codebase to Google’s servers, which are now responsible for compiling their apps into potentially over 100 modules. The Play Store is now responsible for recognizing what a phone needs to provide these modules on the fly. But even if a third-party app store could replicate all of this, there’s a good chance developers wouldn’t be interested in trusting a million different app stores with their signing keys.
Google says Android app bundles save about 20 percent space on average compared to a monolithic APK, which will be a big help for these memory-hungry devices. They’ve been the required standard for phones and tablets since 2021, and in six months TV apps will have to use them too. Developers who don’t switch in time will hide their TV apps from search, so they better get to work! Google estimates that “in most cases, it takes an engineer about three days to migrate”.
Entry image from Google
