I looked in to this briefly a few months ago. Apple seems to be doing it commercially in malls, but the public information is limited. It sounds like it comes down needing to do a custom network mapping of the space, which Apple then pushes in to their mapping databases (server side). There dont seem to be any tools available for the average user to create this data or use it locally.
This kind of leaves Bluetooth tags and your own custom app as the solution for local control, at least in the iPhone space.
I havent looked in to it recently, so maybe things have changed in the last few months. Apple has a website for commercial users to apply or inquire about mapping for their larger spaces (malls, civic arenas).