[asmosoinio]

Thanks for your response. Was this all on Symbian platform? Does that platform give you access just to the active cell, or also the neighboring ones? I wonder if using the full list of neighboring cells could help, that's available at least via Android API.

Nope, it was not ContextPhone. Something for basic phone tracking.

[dirtyaura]

Symbian gave access to the active cell only.

I heard a story that back then this was required by operators, because with good access to neighbouring cells and their signal strengths, people could easily build tools to compare networks in different areas and "prove" that one operator is better than the other. I don't know if the story is true.

You can do very accurate locationing with neighbouring cells and cloud-based database and some simple Bayesian modelling. Google does something similar with their non-GPS locationing.