Android phones, apps and tablets

They telco's and the coppers (if they paid for it) had access to which cell tower(s) you were connected to, and if you logged into specific WiFi access points, but they've not had "to the nearest three metres" GPS coordinates for you- that's a difference surely?

Also the info was generally historical rather than real time.

Not that I really care, to be honest, but it's worth noting that Google increasingly allows us to give up information about ourselves that was either unobtainable, innacurate and/or very expensive to obtain previously.

This is where it gets interesting.

If you only use a 2g network than you are connected to a single tower, in which case you are correct the telcos only know the vague area that you are in.

However, 3g and above make connections to multiple towers and then sends data via the fastest, but with active connections to the others for fallback. Connecting to multiple towers results in very accurate triangulation being possible, and this isn't just possible but actually exists. This data is both historical and real-time.

The interesting bit about the triangulation is that the tower locations are static enough that a map can be created of signal strength to mast identifiers, and the resulting map of the UK with a granularity of below 1m can be shipped in only a couple of MB of data. At Yell we had a company offer to licence us this database for use in a mobile app for legacy handsets, as well as to enable very fast location search even when GPS and WiFi were turned off.

Our use-case was rapid location pinpointing for someone that exits the Underground and was looking for local information... so we expected that the phone would not have a cached location, and that the location services on the device might take 30 seconds to get an accurate location... we wanted to have their location within a couple of seconds and before location services was ready. I should say though, Yell never proceeded with licencing that data, and didn't implement the above.

The map created also details the resulting disturbances in the signal as a result of buildings, and the original purpose of it was in fact to help determine optimal mast location.

The triangulation map increases in accuracy within built-up areas where there are the most masts. And this does include motorway corridors too, as masts generally line those routes. You lose granularity in the country where signals are degraded, perhaps going to 10m accuracy in the Surrey Hills or 1km accuracy in a valley in the Lake District.

So if you are using 3g (most likely, nearly everyone is) and you spend most of your time in cities, then the telcos do in fact have a highly granular record of your location that is more accurate than what Google show you in their app. That record is both historical and real-time.

The major difference between Latitude and telco data is that you can access one, and the other is inaccessible to everyone except government agencies and the telcos.