Writing & Editing The 5 most popular stories on PR Daily this week PR Daily readers thsi week were intrigued by the rise of ‘influencer marketing,’ along with tools and tips for Instagram and Twitter. By PR Daily StaffMarch 30, 2015 SHARE Ragan Insider Premium Content To read the full story, log in. Become a Ragan Insider member to read this article and all other archived content. Sign up today Already a member? Log in here. Learn more about Ragan Insider.