Advertisers are starting to reach US consumers by mobile phone in large numbers, according to the Limbo-sponsored "Mobile Advertising Report", conducted by GfK NOP Research.

Limbo said that 78 million US consumers saw or heard advertising on their mobile phones in the fourth quarter of 2007, despite low overall spending on mobile compared with other media.

"There is a clear disparity between the high reach of mobile media and the low percentage of marketing budget currently spent on the medium, which creates an obvious opportunity for savvy media buyers," said Rob Lawson, president and co-founder of Limbo.

Those who had seen a mobile ad were most likely to have seen an SMS message. Fewer had seen mobile TV and video ads.



Limbo said that widespread SMS usage contributed to high ad reach, with more than half of mobile users saying they used SMS messaging.

Mobile ad exposure was highest among young adults. More than half of 18- to 24-year-olds said they had seen or heard a mobile ad.



SMS messaging is compelling for many marketers because consumers are very likely to pay attention to text messages.

Text messages had the highest rate of interaction for any rich media type measured in PointRoll's "Entertainment Analysis" report. Text messages had an interaction rate of nearly 13% when used as part of entertainment rich media campaigns fielded in 2006 and the first quarter of 2007—more than video, audio or gaming.