https://techcrunch.com/2019/10/01/apple-launches-deep-fusion-feature-in-beta-on-iphone-11-and-iphone-11-pro/

Apple is launching an early look at its new Deep Fusion feature on iOS today with a software update for beta users. Deep Fusion is a technique that blends multiple exposures together at the pixel level to give users a higher level of detail than is possible using standard HDR imaging — especially in images with very complicated textures like skin, clothing or foilage.

The developer beta released today supports the iPhone 11 where Deep Fusion will improve photos taken on the wide camera and the iPhone 11 Pro and Pro Max where it will kick in on the telephoto and wide angle but not ultra wide lenses.