 Viralheat also publishes free application programming interfaces ( APIs ) and two extensions for the Chrome browser . One extension adds a bar to the top of Twitter.com that displays a sentiment analysis of the mentions displayed on the page . A box is added to each tweet showing its assessed sentiment , which can be changed manually . Another extension called " Flint " adds a share button on the browser that can share content being viewed on the browser from sites like Twitter , Facebook or LinkedIn . 
