Someone noticed that their iPhone 11 glows when you turn on the flashlight. The latest models have a special matte glass material on the back. While the iPhone 8 and later have had a glass back, it wasn’t matte and so didn’t produce this effect (Or at least, this is the first time I’ve seen this).
When you turn the flash light on, the iPhone 11 glass back glows. Not sure if the iPhone XR did this too, but I thought the effect was pretty cool.
You can watch it in action on YouTube here.