Lottie files are JSON-based animations that have a small file size, work on multiple platforms, can be scaled without loss in quality, and can include interactivity. You can place a Lottie animation in your InDesign layout and export with in5.

You'll find a variety of free and premium Lottie files available online at lottiefiles.com/featured

Here's how you would add a Lottie file to your InDesign layout and export with in5:
  1. Follow the instructions from the following page to prepare an HTML page that contains your selected Lottie File: https://ublik-om.net/using-lottie-animations-through-iframes/
  2. Use the in5 Web Content interactive widget (in5 > Interactive Widgets > Web Content) and navigate to your HTML file from step 1

If the Lottie animation is a custom one that you've made with tools such as After Effects and the BodyMovin plugin, then make sure you upload it for testing. You won't be able to test it locally.

For more details on using JSON files with InDesign and in5, check out Creating Animation with Lottie Files from Keith Gilbert's Using Animation & Interactivity in Your in5 Project course on Ajar Academy. 

The interface for the Lottie Files website has changed slightly since Keith released his course. Now, to access the code that you would use, you would click the Save to workspace to generate button,

toggle on Enable Asset Link, copy the Asset link,

go to https://lottiefiles.com/web-player, and paste the link in the Your dotLottie/Lottie JSON URL field: