The research firm estimates the average U.S. Facebook user spent 914 minutes on its mobile site/apps in July, +80% Y/Y. That more than offset a 20% drop in PC usage to 351 minutes. Also, Facebook's share of "total Internet minutes spent" in the U.S. (whether PC or mobile) is now up to 15.8%. JPMorgan likes what it sees.
In July (just before the Q2 report), comScore estimated the time spent on Facebook by U.S. smartphone users more than doubled Y/Y in Q2 to 225.4B minutes.
Facebook's mobile ad sales rose 75% Q/Q in Q2 to $656M, and made up 41% of total ad revenue.