Mobile traffic on YouTube increases from 6% in 2011 to 40% YTD 10/18/2013 - 00:00 It’s hard to get people to concentrate long on anything on their phones and tablets, yet YouTube seems to be the exception. The video service is quickly going mobile, with small screens making up 40% of its traffic now compared to 25% last year, Google said on its earnings call today. In 2011, just 6% of YouTube traffic came from mobile.