Clone Hero release information has included iOS availability, but iOS distribution should not be treated like Android APK installation. The safest approach is to follow the current release method for Apple devices and avoid unofficial repackaging.
Do not use Android APK instructions on iOS
APK files are Android packages and are not an iOS installation format. Treat iOS as its own platform with its own distribution requirements.
Quick validation
Change one variable, test it immediately, and keep the working state before moving to the next adjustment.
Confirm the current release method
Apple-side signing and distribution can change between releases, so check the current release notes before assuming an older installation path still applies.
Verify controller support before building a setup
Test whether iOS recognizes your intended gamepad or instrument connection method, then check how the game exposes those inputs for mapping.
Keep mobile storage in mind
Leave enough free storage for the game, custom charts and updates. A large songs library can be the dominant storage requirement.
Calibrate for the actual audio route
Wireless audio can introduce noticeable delay. Use the same headphones or speakers during calibration that you plan to use during play.