• by Erik Sass , Staff Writer @eriksass1, August 20, 2015

Growth has slowed for both Facebook and Twitter in the U.S., at least in proportional terms, according to a new study from Pew Research Center, titled “Mobile Messaging and Social Media 2015.” The report is based on a national survey of adults over landlines and cell phones.

The proportion of U.S. online adults who use Facebook edged up from 71% in 2014 to 72% in 2015, Pew found; the last substantial increase was in 2012-2013, when the proportion increased from 67% to 71%.

From 2014-2015, the proportion of U.S. online adults who use Twitter remained steady at 23%, after increasing from 16% in 2012 and 18% in 2013. (Overall, Pew found that 85% of U.S. adults are online, while 67% own a smartphone.)

70% of Facebook users say they use the site daily.

Some other, newer social networks are continuing to grow at a faster clip: the share of the U.S. online population using Pinterest increased from 28% in 2014 to 31% in 2015, while the proportion using Instagram grew from 26% to 28%.

Moreover, 59% of Instagram users say they use the site daily, while 27% of Pinterest users said the same.

However, it wasn’t all good news: The proportion using LinkedIn actually decreased from 28% to 25% over the same period; 22% of LinkedIn users said they use it daily.

On the mobile messaging front, Pew found that 36% of smartphone users said they used messaging apps like WhatsApp, Kik, or iMessage, while 17% use apps that automatically delete messages, like Snapchat or Wickr.

The proportions are higher among younger U.S. adults, with 49% of smartphone owners ages 18-29 using messaging apps, and 41% using apps that automatically delete messages.

Turning to blogging platforms, 10% of online adults use Tumblr, up slightly from 6% in 2012. However the proportion was significantly higher among younger adults, with 20% of the 18-29 age set reporting using Tumblr.