Access RB5 hardware through AOSP app


I have built AOSP from source using this manual and created a custom service that allows for interacting with the LEDs on the board (I have tested this service with a test client). How can I access this service via a “stock” app that is part of my AOSP build? I have tried folliwing guides online without success and I have tried to make a copy of an existing app (Calendar) by duplicating everything related to Calendar and renaming it (this compiled but I see no trace of the app). I think that I have misunderstood something fundamental.

I apologize if this question is to big or if I provide to little information and I am helpful for any help I can get.