If your goal is specifically to play Wii U games, your best bet is to use a PC or Mac and download the official version from the Cemu GitHub project.
If you want to play retro games on your iPhone, stick to verified emulators available on the App Store or reputable side-loading sources: : Great for NES, SNES, N64, and GBA. cemu ipa
While there is high demand for a (a file that would allow the Cemu Wii U emulator to run on iOS devices like iPhones and iPads), no official or stable Cemu IPA currently exists The Cemu development team focuses exclusively on If your goal is specifically to play Wii