APK, AAB and source: three different deliverables
Android development produces several things that can look like “the app,” but they serve different jobs. Keeping source, testable packages and store distribution artifacts distinct makes a build workflow easier to reason about.
Source is the editable product history
Project source contains code, resources and configuration needed to continue development. A generated binary without usable source may be installable today but difficult to repair tomorrow.
APK is useful for direct testing
An APK can be installed on compatible Android devices and is convenient for physical testing during development. That makes it valuable for checking behavior before a store release.
AAB is designed for distribution
An Android App Bundle is a publishing format used by Google Play to generate optimized packages for devices. It is not simply a differently named APK, so a build workflow should make the intended artifact clear.
Signing belongs to the release process
Release builds involve signing identity and versioning. Those details should be treated as durable release configuration rather than last-minute switches added after development is finished.
Why DroidBake keeps the distinction visible
A creation tool should make it clear whether it has produced editable source, a testable build or a distribution artifact. Keeping those outputs connected makes later repair and verification easier.