This is probably a reference to the integrated motion tracking support[1]. Sure, you can use any 3D application to generate content for AR, but it's a lot easier to overlay 3D object into an existing scene when the 3D application can process a video and automatically adjust the camera parameters to match.
Any 3D application is useful for the former so I'm not clear on what specifically you're referring to.
If you mean the latter then I'm aware of a "edit inside VR" add-on for Blender but unclear on what the AR connection might be.