Snapchat's new Discover feature is a big update.It allows Snapchat users to view news in the form of Snapchat Stories. After 24 hours, the stories disappear and are replaced with fresh content.To cover a wide range of interests, Snapchat has partnered with CNN, Vice, Yahoo News, Comedy Central, National Geographic, Daily Mail, ESPN, Food Network, and Cosmopolitan. Here's how it works.