Washington - Twitter is finding a niche among younger US adults who monitor the messaging service for news on mobile devices, a survey showed.The Pew Research Centre report said 16% of American adults use Twitter, and that much of what gets passed on is breaking news.Some 52% of Twitter users say they use it for news. That means some 8% of US adults are Twitter news consumers, the survey found.While Americans use other social networks such as Facebook to follow news, "Twitter news consumers stand out as younger, more mobile and more educated," the Pew report said.Among the Twitter news consumers, some 85% said they get news at least sometimes on mobile devices. That outpaces Facebook news consumers by 20 percentage points.EducationPew also found that 45% of Twitter news consumers are 18 - 29 years old - more than twice the percentage among the population overall and well above the 34% of Facebook news consumers in that age group.Twitter news consumers also tend to be more educated than the general population and than Facebook news consumers, Pew said: 40% have at least a bachelor's degree, compared with 29% of the total population and 30% of Facebook news consumers.A separate analysis of Twitter news sharing shows many of the conversations focus on breaking news and that sentiment can shift quickly.For example, in the two weeks after the March 2013 Supreme Court hearings on same-sex marriage, Twitter sentiment was opposed to the idea of legalising same-sex marriage by 55% to 32%; but a month later, Twitter sentiment had reversed and favoured same-sex marriage 43% to 26%.Pew said that while sentiment on Twitter can sometimes match that of the general population, it is not a reliable indicator of public opinion.It noted that Republican candidate Ron Paul easily won the "Twitter primary" in the 2012 presidential race with 55% of positive remarks, but he failed to gain traction in real primaries.After the Newtown, Connecticut, school shooting, 64% on Twitter said they supported stricter gun controls, compared to 21% in opposition. But public opinion survey after the tragedy was mixed.This two-part report is based on a survey of more than 5 000 US adults from 21 August to 2 September. The margin of error ranges from 1.7 to 4.6 percentage points.