Retrieving Geo information from a Mobile Phone

While skimming through Bernhards [1] entry I got stuck at the second part of the post, where he notes:

The whole thing is very GPS oriented, which kind of puzzles me [..] So I will have to ask someone for a GPS device to try it myself [..]

As far as I understood that background, it is about getting localized information from mobile gadgets as on tokyotidbits.com [location info, 2]. As I have no GPS around here and do not at all intend to carry one around with me – at least as a seperate tool – I thought that there might be a way to get some localized information out of the mobile phone.

At least on my mobile phone and with the telephone company\’s help there is a way to get the \”Zelleninfo\” (Cell Broadcast, CB ) [3] – an information about the place of the most closest antenna, or at least the one with the best signal. You can most probably enable that bit of information to be displayed on the phone via a subcategory of the SMS menu.

So, what we get there, is something like \”BERN WEST\” – far from being as precise as a GPS. But imagine to combine such information with moblogged images; that would result in an interesting track along your image gallery.

But how can we get that info out of the phone and back to a webservice. CB is a monolog. It works from the emitter to the receiver (mobile phone). As long as there is no way to attach that localized info directly to an SMS or something, your hands are tied. Ok, there might be a way to hack the mobile software or writing a java application maybe. Is there a workaround?

Maybe, if we have a look at the WAP protocol [4]. What about this way?

  1. Send a message from the phone X to a server; e.g. blog a picture
  2. Handle the request on the server
  3. Sending a request back to the phone X, asking for the CB info
  4. Handling that info and adding it to the image as localized info

Well, that won\’t work. The connection gets probably lost after having sent the picture. We would need something like a session and being able to backadress the phone. Why not keeping that fist connection?

[1] http://www.bernhardseefeld.ch/archives/000030.html
[2] http://www.tokyotidbits.com/archives/000341.shtml
[3] http://www.ascii-logos.de/facts%2Binfos/sms%2Bcb/cb-info.php
[4] http://www.wapforum.org/what/technical.htm

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