The deluge of stories revolving around Facebook copying Snapchat might hit a zenith today as the social media company begins to launch "Facebook Stories" worldwide, this time in the main Facebook app for iOS devices (via TechCrunch). Previously, Facebook created a facsimile of Snapchat's day-long, vanishing post idea in Facebook Messenger, WhatsApp, and Instagram, which gained 100 million users following the Snapchat-like update last year.