Locate an iPhone reliably indoors?

Question

I\'m writing an app for a museum tour. I\'d like my app to know where the user is in the building, if the user is standing in a particular room, in front of a particular work, e

Answer 1

Can you manufacture some small device for the task? ie making an IR receiver that can identify a IR emitted code and make a sound signal for the iPhone to interpret through the headphone mic plug.

Here is a pure mic but I think it could be made with an IR sensor instead.

And...here is a product that does both sensing IR signals and emits IR. Redeye mini. Then you will need some sender devices for the rooms and perhaps near a particular work.