APK stands for Android Package (sometimes Android Package Kit or Android Application Package). This is the file format that Android uses to distribute and install applications. As a result, an APK contains all the elements that an application needs to be properly installed on your device. AABs (short for Android application packages) address some of the serious inefficiencies of APK files.
Like APKs, AABs are also used for the distribution of Android applications. These are Android files that mark the progression of the use of APKs for the installation of applications.
Android app
bundles are a new application compilation format with much greater efficiency than a normal APK. Although, ultimately, the devices will still receive an APK, each will be specifically adapted to the operating system version, the device format, and the active regional settings. Application packages are a publishing format, while the APK (Android application package) is the package format that will eventually be installed on the device.An APK contains a compiled version of an application, along with critical multimedia resources, such as icons and sounds. Because the App Bundle system focuses on dynamically generating signed APKs in the cloud, developers must hand over their application signing keys to Google. The applications are installed directly on any device, however, the Apk files must be installed as an application after downloading them from any reliable source. Instead of developers signing app updates to their own build infrastructure, Google will take an application package and convert it into signed APKs. An application is a mini-software that can be installed on any platform, be it Android, Windows or iOS, while Apk files can only be installed on Android systems.
You might wonder why the APK saves both a copy of the compressed version and another copy for the uncompressed version. Since Google already has the keys needed to generate new APKs, it could remove the transparency file from the code whenever it wanted. If a developer wants to offer more optimized builds, they must manually compile and sign several different APKs. By using a traditional APK, the application will receive all the assets and will only choose and use the ones that are necessary for that specific device. The APK format does not adapt to this diversity, since each package contains all the application's resources.
Since AABs will soon become the norm in the Android ecosystem, it's best for most developers to move away from APKs for submitting applications. We are all well aware of the term application, which means Application, but only a few of us know Apk. In addition, code transparency is completely optional and is only enabled when the APK includes a transparency file. The application packages are in a publication format, while the APK (Android application package) is the package format that will eventually be installed on the device. Considering the various advantages of AAB files, it's naturally advantageous to choose them instead of an APK compilation.