[nostrademons]

A lot of workplace usage has shifted to mobile. Many workplaces will monitor all your Internet usage, and so once mobile became available, many people decided that rather than letting their employers know how much time they waste during the day, they'd use their own private Internet connection for that.

We saw a similar effect at Google with porn queries, particularly during the day. As soon as image search came to mobile Google, many porn queries moved to mobile; as of 2013 porn queries were twice as likely on mobile search as desktop.