Better Wallpaper Support
Although it’s always been possible to use any image you like as a wallpaper, there hasn’t really been any way for a third-party app to do this beyond dumping photos into your Photos app and then making you pick them from there. Similarly, if you wanted a collection of custom wallpapers, your only option was to create a photo album of them and pick them from there.
However, it appears that iOS 14 will finally offer better organization of images in the Wallpapers settings, not only letting you add and organize your own images, but also extending the ability for third-party developers to offer custom wallpaper collections.