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From October 2012 to October 2014, 42% more people consumed sports on their mobile device. In 2014, the average American consumer spent 99 minutes on sports content, a 35.6% increase from 2012 (73 minutes). The top five sports apps are ESPN Sports Center, MLB At Bat, Team Stream, NFLMobile, and Yahoo! Fantasy Sports - Fantasy Football.
Perhaps bigger screen sizes on smartphones have contributed to this increase in sports consumption on phones. If people are watching live sports on their phone - rather than just sports talk shows - then they would need a sizable screen.
I completely agree. Also, between 2012-2014 video streaming technology grew tremendously. Not much of a difference now between watching something on your phone or computer.