My app currently doesn't specify multiple different appearances (Any, Dark, Tinted) for the App Icon. I want to release an update in which I plan to create a new AppIcon resouce which is going to contain these 3 appearances so that users on iOS 18 can have better experience.
Once I will provide the new App Icon with the Any, Dark and Tinted variants, which of these variants will the App Store use for my app on the App Store? Does it depend on the user's system-wide choice of appearance? That is, would the App Store show a different icon appearance for my app for a person using the "Dark" option and a different app icon for the person using the "Light" option?
Can I force the App Store to always display the "Any" variant of my icon on the App Store, regardless of the user's dark mode setting?
My app targets iOS 13. What would happen if a person running iOS 13 would install the new update of my app, which newly contains all 3 App Icon color appearances? Would the "Any" variant be displayed and would iOS 13 ignore the "Dark" and "Tinted" variants? Or is there no backwards compatibility and older iOS version would display a blank app icon (the icon used by iOS for apps, which do not specify an App Icon)?
P.S. Is this documented somewhere? Perhaps in a WWDC video or in documentation? I could not find enough in-depth information on this topic (especially on app icon appearance behavior on iOS 17 and older).