eMarketer help online media people sell more digital media, published this research in one of their releases.
Sourcing the document quoted at the bottom of the graph, Wayne discovered the following:
"Traditional media were the biggest motivation for beginning a search on a SmartPhone, followed by word-of-mouth."
With respect to Mark Twain, "The death of traditional media has been greatly exaggerated".
You can find the full eMarketer report here.