Wolfenstein 3D and the oft-forgotten Wolfenstein RPG were both available on iOS back in 2009, with a version of Wolfenstein RPG also being available for Java-compatible phones. Unfortunately, neither title was updated to keep up with the operating system's major updates and are no longer available to play normally.
Zeal has released a video showcasing how to get both versions of Wolfenstein RPG working and playable through emulation on Windows, which can be adapted for the iOS version of Wolfenstein 3D as well! This guide won't cover that (yet?) though, and you'll need to find your own copy of Wolfenstein 3D for iOS (Only v1.0 works).
Find Zeal's YouTube Channel at https://www.youtube.com/@ZealedGuy