I followed your Documentation for Native Android.
I created the wtc file via the Wikitude Studio Manager.
When a developer is building his app with Native API then this is entirely up to him to program how he wishes his app to behave. The Native API wraps the main functionalities of the Wikitude and enables the full computer vision power in your app. To keep it lean, the Native API does not integrate a separate rendering engine, but offers you the full flexibility in terms of rendering augmented reality content.