I saw these during a holiday in Spain throughout the last week. I have no idea how to use them and didn't see anybody else use them either. It would probably be a different story if my phone had some kind of built-in support for this stuff (maybe it does?). I recall using the "Google Goggles" app for this kind of thing a _long_ time ago but it should be native - and obvious - by now.

I have a feeling that the industry has stopped depending on this stuff already... it's hard to tell without knowing how it works.