NEW YORK/SAN FRANCISCO: Facebook and Twitter are stepping up their efforts to increase their share of the global TV ad budget as technical developments begin to enable advertisers to target people who use digital devices while watching TV.

As reported in the Financial Times, the two social network giants have been rolling out a number of initiatives over the summer in a bid to earn more from global TV adspend, which is expected to be worth $205bn this year.

Facebook has launched a campaign, dubbed "reach for the beach", to highlight the fact that holidaymakers take their mobile phones with them while leaving their TVs at home.

It comes as recent research from eMarketer has shown that the amount of time people in the US spend consuming digital media will overtake the hours they spend watching TV for the first time this year.

Carolyn Everson, Facebook's vice-president of global marketing solutions, said mobile has overtaken TV to become "the primary screen", although she didn't expect TV and Facebook to be locked in rivalry. "I think we're at a stage where the conversation is really TV plus Facebook," she said.

The company has commissioned a study from Nielsen, the market research firm, which found that more people aged 18 to 24 used Facebook than any of the four major US TV networks between 8pm to 11pm during weekdays.

It is currently developing 15-second video ads that can replay TV ads on Facebook and plans to launch the initiative in October. It is also working on the means by which ads on Facebook could be linked to a TV show in real time.

Twitter, meanwhile, has formed partnerships with media companies to monitor what people tweet while watching TV and it expects to use the information to help target ads on Twitter.

Adam Bain, Twitter's chief revenue officer, said: "We often have thought about Twitter plus TV, but we are now thinking about Twitter times TV."

However, advertisers are weighing up the pros and cons of linking in their offerings to the social networks.

Joe Mele, a senior vice-president at Razorfish, the Publicis-owned digital marketing group, cautioned whether consumers would want to receive ads while tweeting, for example, about the presidential debates or the Super Bowl.

He said: "There is a question about whether or not just because you are watching something on TV means you want that same experience on a different device."

Data sourced from Financial Times; additional content by Warc staff