Viewers in 10 cities across the country including the four metros, will soon be able to watch Doordarshan and 19 other channels offered by Prasar Bharati on their smartphone, tablet or laptop for free.

Officials said the national broadcaster has charted out an aggressive plan to expand the range of its mobile TV services to at least 40 major cities and the services are likely to start in the first 10 cities before the end of year 2013.

"Prasar Bharati has experimented with Mobile TV service in the past also and in 2007 a pilot project had been set up in Delhi. However the technology used at that time only allowed signals to be transmitted within a radius of 10 kilometres.

"The technology that will be used now will be