I know we could change the app icon of the application in iOS 10.3 above and I achieved this successfully, but my question is that could we achieve this using a custom url.
Suppose that the app icon is stored in the backend server and the icon while changed according to the user login in the system. Is it possible?
This is not possible. Any alternate icons must be predefined the the app's info.plist file and are subject to app review.
Check out the documentation here: https://developer.apple.com/documentation/uikit/uiapplication/2806818-setalternateiconname
Apple's Human Interface Guidelines discusses some of the limitations of custom app icons: https://developer.apple.com/ios/human-interface-guidelines/icons-and-images/app-icon/
