Mobile consumers believe that engaging with one minute of advertising on mobile devices is equivalent to £6.80 per consumer for advertisers, a new report has found. The international study of 4000 people, conducted by Opinium Research and commissioned by Millennial Media, found 79% of consumers understand that ads keep content and apps free, with only three percent paying for ads to not appear on their mobile devices. Almost three-quarters (72%) said they expected mobile ads to keep content free.