Recent versions of Android support direct access of native library files (.so) from the APK on the filesystem. This is significant to reduce install size, as well as simplifying the case where an app is pre-installed on the phone (i.e. only .apk file needed).
Requirements are that the .so files be stored uncompressed in the zip, and properly aligned.
Unity Android build appears hard-coded to store .so files compressed. Would like an option to store them uncompressed, and perhaps also apply the zipalign tool and set extractNativeLibs=false in the manifest.