The UK's first mobile network to be supported by advertising has gained 100,000 customers six months earlier than expected. Blyk, founded in 2006 by Pekka Ala-Pietila, former president of Nokia, launched its service in September last year, writes Tim Bradshaw .

Blyk only accepts customers aged between 16 and 24, who agree to view adverts in exchange for credits for free calls and text messages - a demographic particularly attractive to advertisers.