An APK is an Android Application package file. Gradle, by default, builds a single APK, no matter what libraries you include. This compiled and packaged file includes all of the application's code (.dex files), manifest files, resources, and assets.
The library, within itself, comprises multiple copies of the same native code, optimized for the different architecture. This means that the library is a native binary with multiple architecture such as x86, x86_64, armeabi, and so on, all packed together. A developer can easily run the command unzip <your_APK_name>.APK to understand the content of an APK:
When your app, and the libraries it references, reaches a specific threshold, you encounter build errors that point to the app's limit of the Android App Build Architecture. The most recent Android build system displays an error, trouble writing output...