What on earth is this all about?
Don’t you mean “Where on earth?” (sorry). Location-based services – or LBS, to the initiated – help you find out where you are or where something else is when you’re out and about in town, or even lost out there in the big wide world.

Clever. How’s that work then?
Just imagine your mobile phone contains software that works like a tracking device, so if you want to know where the nearest cinema is the information can be sent to you right after your phone has been located.

Tracking device! Can I be followed without knowing it?
That is an issue but there’s little to worry about while services remain pretty basic.

Is this location finding stuff just another mobile gimmick, like WAP?
Not really. Some people say LBS are the key differentiator between mobile and fixed line networks because they open the door for tailor-made content. Seven out of 10 people surveyed by Forrester Research in September 2000 who voted for future mobile phone services favoured content that required location-based technology to work.

I’ve heard of Global Positioning System – GPS – is this the same thing?
In terms of end results, pretty much, yes. GPS can be one part of the LBS equation. It’s expensive as it uses satellites to beam your location directly to a GPS chip implanted in your phone. Plus, to work it requires direct line of sight so it’s no good indoors or in your briefcase unless you’ve got the Enhanced version, which is even more expensive as it uses one of the ground-based location technologies, so entire networks have to be fiddled with.

Sounds terrible!
It’s alright, it doesn’t get worse. There’s another technology called Enhanced-Observed Time Difference (E-OTD). Without being GPS, it’s the most accurate location tech but operators need to spend a packet on buying new networks and handing out new phones, so it’s a bit of a no-go when all the money is being pumped into 3G licences, networks and handsets.

So what’s the best technology?
Basic Cell ID is being used a lot today as it’s already inside your phone. It works by identifying the base station that is supplying the best signal at a particular time and assuming you’re somewhere in that cell, just like when it connects you to an incoming call. Even though the accuracy depends on the cell size, it’s cheap as you don’t need to update your handset or the network’s base stations. Many Europeans believe Cell ID is great as it’s enough to let you know the location of what you may not be able to see but are close enough to walk to.

Is anyone keeping an eye on all this development?
In the US there’s a mandate called Enhanced 911, or E911, that says operators should be able to pinpoint a person in an emergency situation through their mobile phone. This mandate is pushing those in the US to focus hard on accurate location, although all the operators have missed the mandate deadlines for compliancy since 1996 due to technical obstacles. In Europe there’s also a deadline but it is way off at the other end of this decade (2008) so operators can wallow in the joys of content provision for now. But they still realise the value of getting LBS truly off the ground, and we’re bound to see more of it.

For a complete list of Cheat Sheets type ‘CS1’ into the silicon.com Search

**Essential Links**
Location Interoperability Forum
Groups: Location-based services

And from the silicon.com archive:
Location location location: Where the mobile industry is pinning its hopes
and AirFlash merge to lead the way