The number of people accessing social networks via mobile devices in the U.S. increased from just over 40 million in March 2010 to around 60 million in March 2011, for a percentage increase of 45.7%. That’s even bigger than the increase in high-demand categories like weather, which grew 40.2% to just over 60 million, and personal email, which grew 30.7% to 70 million. Mobile search increased 32.1% to around 55 million, mobile news increased 38.1% to 45 million, and mobile maps increased 43.3% to 45 million.