Former Nokia CEO Olli-Pekka Kallasvuo has joined Swedish TV software company Zenterio as chairman of the board.

Kallasvuo, who headed the Finnish company in 2006-2010, when it was the world leading cellphone maker, told The Associated Press he aims to promote an operating system for interactive TV sets on a global scale.

He says in an interview Thursday that the market includes 650 million customers who are increasingly using TVs to connect to the Internet.

He noted "the market of operating the software for the set-top boxes and TVs is extremely fragmented."

Zenterio, launched in 2002, said former Sony Ericsson CTO Mats Lindoff has been named chief technical officer. Based in Stockholm, its customers include TV operators, global systems integrators, TV and set-top box manufacturers and chip makers.