Is Your Mobile Website Ready for April 21stIt’s another big year for mobile. Just how big? Mobile ad spend is going to surpass desktop for the first time ever.

“This will be a benchmark year for ad spending in the US, as mobile surpasses desktop spending for the first time,” reports eMarketer. “Mobile will account for 51.9 percent of total digital spending in 2015. That’s a higher figure than eMarketer forecast earlier this year.”

It’s true. Desktop’s share of advertising dollars is declining and mobile’s share is growing robustly.

Expectations are that “mobile advertising (will) grow by 59 percent in 2015, a higher rate than forecast in March, when (we) last released figures for US ad spending.”

“Brands and marketers continue to see increased value in mobile advertising to reach consumers,” said eMarketer analyst Martín Utreras. “Some of the shift is happening organically from digital ad spending dollars, but also we see additional dollars moving from traditional media and new money coming from local advertising and small businesses.”

The shift to mobile ad spending is being driven mainly by consumer demand.

Time spen on mobile is growing: eMarketer estimates that U.S. adults are spending 2 hours and 51 minutes each day on nonvoice activities on mobile devices. More than half of that, about 1 hour and 31 minutes, is spent on mobile phones.

“Consumers’ increasing on-demand consumption of media through mobile — coupled with improvements in targeting, attribution and ROI for mobile advertising — will continue to take away ad dollars from magazines and newspapers,” said Utreras.