ComScore, a leading digital metrics company, today released details from its report on social media brands. The results were obtained using comScore’s new mobile behavioral measuring service, which the company calls “Mobile Metrix 2.0.” Using the measurements, comScore was able to rank social and other websites based on the number of unique visitors from smartphones in March 2012.

Not surprisingly, Google topped the rankings with nearly 94 million unique visitors. This means that nearly 97% of all smartphone users visited a Google site in March. Google is trailed by Facebook, which had around 78 million unique visitors, or about 80% of smartphone users. What’s interesting about these numbers, however, is that smartphone users accessed these sites from apps, rather than web browsers, about 80% of the time. This is a trend followed for most sites listed in the chart seen below. It appears that smartphone users prefer to segregate their web browsing by using app interfaces and overlays.

ComScore also compared the most popular mobile apps for iOS and Android users. Both lists were fairly similar, with each platform’s respective app market, Google Maps, Facebook, and YouTube in the top-five for both. It’s also clear that the pictionary-style game Draw Something was a short-lived fad, appearing nowhere on the list just a month after being sold to Zynga.

Though Google’s search, Maps, and YouTube apps give it the overall edge for smartphone visitors, no social networks come close to Facebook. The world’s most popular social network beats runner-up Twitter by a three-to-one margin with its previously mentioned 78 million unique visitors. Facebook also dominates when it comes to user engagement, averaging 441.3 minutes per visitor each month.

Though these numbers are not totally surprising, they are instructive. The fact that smartphone users prefer apps over web browsing shows just how ingrained Apple’s app system has become in smartphone culture. It won’t be stopping with smartphones, either: our desktop operating systems and TV sets will soon be “app-enabled.”

What do you think about these comScore numbers? Leave a comment below and let us know.

(picture courtesy of Google)