In the US roughly 40 million mobile users access social networks (broadly defined to include blogs) on their handsets on a daily basis, according to comScore. The large number of mobile-social users comes as no surprise. Facebook previously announced it had 350 million active mobile users globally.
Google also sees mobile as a strategic front for social networking growth. The new version of Android (“Ice Cream Sandwich”) prominently features Google+.
The chart below shows comScore traffic estimates for mobile usage of Facebook, Twitter and LinkedIn. Facebook has many more mobile users than the other services, although I assume comScore underestimates the number of actual mobile users across the board.
For example, Twitter recently said it had 100 million active mobile users. It also said, “46 percent of active users make mobile a regular part of their Twitter experience.” That would mean 46 million mobile users at least for Twitter. If 60 percent of Twitter users come from outside the US we can crudely estimate that there are just under 20 million mobile Twitter users in the US.
Overall comScore says the mobile-social networking audience in the US is just over 70 million people. The total mobile internet audience is now over 100 million people in the US according to data from Nielsen.