by Jack Marshall, Digiday

“According to social ad-buying software provider Kenshoo, mobile now accounts for over 20 percent of Facebook ad revenues, for example.

Despite the progress, the fact remains that a clear revenue gap continues to exist for the vast majority of publishers. For companies like Facebook and Twitter, it might be closing, but it still presents a significant challenge, and its size remains unclear.”

Read the full article on Digiday.com