About 6 billion people had cellphone subscriptions at the end of 2011, but there were still a billion who did not, a United Nations agency report said.

The number of people with mobile phones is increasing rapidly, with the International Telecommunications Union report indicating double-digit growth in cellphone subscriptions in developing countries over the last year, the Chicago Tribune reported Thursday.

An estimated 2.3 billion people have access to the Internet, the report said.

But mobile Internet services are growing, with twice the number of mobile broadband subscriptions as there are fixed broadband subscriptions worldwide, the ITU said.

That's due to the growth of mobile broadband and affordability, said Susan Teltscher, head of ITU's ICT Data and Statistics Division.

"We have been monitoring ICT [information and communication technology] prices now for four years, and there has been a 30 percent drop in the price of ICT in the past four years," she said.