Owner of O2, is launching a new division to sell information about its customers.
9 October 2012
Telefonica Digital Insights will offer companies and public sector bodies "analytical insights" based on users' anonymised location data.
It hopes that exploiting such "big data" will help revive its flagging fortunes after falling sales.
But doubts remain about how accurate and useful such insights will be.
The division's first product, Smart Steps, will provide retailers and other bodies with location "heat maps" of mobile phone users' movements throughout the day.
"Using our aggregated and anonymised mobile phone mast data we can provide retailers with a digital headcount to help them understand the movement of crowds," a spokesperson told the BBC.
"Retailers are quite good at measuring footfall inside their stores, but this data will tell them where people go once they are outside, as well as their age and gender."
Retailers already buy footfall data from specialised companies, such as Springboard and Experian, so it remains unclear how Telefonica will add value to existing services.