There's a really cool feature in iOS 13 that allows you to watch a series of concurrently taken Live Photo's simultaneously as one long video.
I noticed this a few weeks ago when I was watching a Live Photo and it kept on going through the others I took. It took me a few minutes to realize what was going on.
As a bonus, you're also able to select a group of those same Live Photos and extract them as one long video.
This is a huge feature I hadn't heard about before stumbling upon it. I almost always shoot with Live Photos enabled in case something happens that I want to turn into a GIF later. Can't wait to see what other hidden gems are in the release.