Just downloaded the latest build in order to start using the new icons structure for iOS 11 (Images.xcassets).
I noticed that there is an issue when building the App project template via Xcode.
Although the project has the Images.xcassets configured correctly, I noticed that the project is always getting the "Corona/Icon.png" as its icon, ignoring all icons from Images.xcassets.
Based on what I read, I think that "Corona/Icon.png" file should not even exist anymore, but if you remove it, the App gets installed without icon.
If you build the template app via Corona Simulator, it correctly gets the icon file from Images.xcassets.
You can replicate that problem by just downloading the latest build (2017.3160) and open the App.xcodeproj and build it to the device. You will notice that the icon will be with a low res (since the Corona/Icon.png has only 57x57). If you delete that icon, the app will be installed without icon. (Just don't forget to "Clear" the project before building after deleting the icon file)