Today, Microsoft announced that OneDrive now supports Live Photos on iOS. If you've got automatic camera backup enabled, the service will begin uploading your Live Photos as they're intended to be. Up until now, they've been uploaded as still images.
Microsoft is also adding Live Photos playback to the app. When you open a Live Photo, you can tap and hold the photo. You can also play your Live Photos on Onedrive.com by clicking on a 'Live' badge in the top-left. Unfortunately, they'll still show up as still photos on Android and in the Windows Photos app.
Of course, Live Photos have been around since the iPhone 6s was introduced in 2015. That means that you could have five years of Live Photos that are stored as still images. Luckily, Microsoft is providing an easy and handy way to fix that.
In the OneDrive app on iOS, go to the app's settings, and then go to Camera Upload -> Reupload from Original Formats. After that, it will upload all of the Live Photos in your library.
Unfortunately, editing Live Photos is still not supported. If you edit a Live Photo, it will be saved as a still image and you'll lose the original format. You'll be able to restore the previous 'Live' version for 30 days.