Its always been there but maybe you've never seen it before. This works with LIVE PHOTOS taken on iOS. I don't know if this works on Androids. Sorry, folks!
Step 1: Open up your Story Camera
Step 2: Upload a Live Photo. Look for the Live Photo icon
Step 3: Hold your finger down on the image until it turns into a moving photo boomerang omg its so cool I know. You're welcome!
Tutorial Produced with EcammLive