phone with WAP browser would count as a 'location-aware device'; standard services allow you to locate nearby pubs; in urban areas, the few hundred metres accuracy available per cell ID suffices for this, in a blunt-instrument way. but the device-location mapping isn't open or free; available for re-sale, for bootstrapping commercial services.
...and Cellspotting.com answers it:
“CellSpotting.com" is a global location based service for mobile (GSM and soon UMTS) users.
Use CellSpotting to find information for the place you are at!, and even better you can help and give information to others about places you know! CellSpotting is a Collaborate Location Based service built by its users. [...]
- Find the name and location information about a place you are at.
- Track your Cellspotting friends, You can find the whereabout of your friends.
- Find the distance and direction to spotted cells!
The applications Cellspotting proposes are pretty mundane: tourist information, local interest groups, maybe a “jazz clubs near me” and other types of categorized services. And there's no discussion of ownership of content and/or the social ramifications of using collaboratively generated, potentially inaccurate, kind-of-spotty location data to lookup your friends and loved ones. But it's interesting how accepting uncertain, incomplete, and potentially flawed data from a whole lot of people might enable "good enough" location-finding in the public domain. The problem is recruiting enough sources -- and how open Cellspotting is to letting outside developers use their database.
Coverage of the US is unsuprisingly poor, but the scope of the project -- spanning carriers and continents -- is impressive, especially given that the client only runs on Nokia Series 60 phones.