• by Joe Mandese  @mp_joemandese, July 18, 2016

Mobile will replace "fixed devices" -- including desktop -- as the dominant platform for accessing online video, according to a new forecast released this morning by Publicis’ Zenith unit.

“Consumers around the world will spend an average of 19.7 minutes a day viewing online videos on their mobile devices (smartphones and tablets), compared to 16.0 minutes on fixed devices (both desktop computers and smart TV sets),” the report estimates, adding: “This represents a 39% leap for mobile on last year’s figures, when 14.2 minutes were spent viewing mobile video.”

By comparison, Zenith estimates “fixed” video consumption will be static this year, thanks to a rise in viewing via smart TVs, which offset declines in desktop viewing.

The report -- the second annual Online Video Forecast to be published by Zenith -- covers 57 markets, up from 40 last year.

“We forecast mobile video consumption will grow 33% in 2017 and 27% in 2018, to reach 33.4 minutes a day,” the agency predicts, adding that "mobile devices will account for 64% of all online video consumption in 2018."

Not surprisingly, Zenith also anticipates an upswing in online video ad spending, which should increase about 20% per year.

Advertisers spent $17.5 billion on online video ads in 2015, up from $13.4 billion in 2014, according to the agency’s estimates.

“We forecast online video ad spend to grow at an average rate of 19.8% a year, reaching $30.1 billion in 2018,” the report concludes.