Since the Wii U used a "Second Screen" concept (the GamePad), it is naturally suited for tablet/phone streaming.
As of now, a functional, native Cemu emulator for iOS remains unavailable to the general public. The hardware is ready, but the software environment remains restricted. Until Apple relaxes its stance on JIT compilation or the Cemu team decides to prioritize a Metal-based ARM port, streaming from a PC remains the only viable way to enjoy Wii U games on an iPhone. Cemu Wii U Emulator Ios
The official Cemu website does not list iOS as a supported platform. Since the Wii U used a "Second Screen"