Hello all!
I am currently facing an issue where I am receiving an "ios app products are only permitted in swift playground packages" error when trying to build the app. I forked a branch from the git repo that my friend made not too long ago, yet I still can't figure out what the issue was. I can provide the repo if needed.
It sounds like the package you forked from was made for use in Swift Playgrounds! That means it will have an iOSApplication product, which is only usable in the context of a Swift Playgrounds application.
If you add the .swiftpm file extension to the folder that contains the package, you can open it in Swift Playgrounds or Xcode and use it as intended. If you don't use the iOS application product and don't want it, you can edit your Package.swift to remove it from the list of products.