> This allows Apple to switch to intel chip on iPhone, or switch to an ARM chip on MacOS. Not easily. It's optional on iOS [1], and doesn't support completely

> This allows Apple to switch to intel chip on iPhone, or switch to an ARM chip on MacOS. Not easily. It's optional on iOS [1], and doesn't support completely new (non-ARM) CPU architectures. On macOS, the feature doesn't exist at all. [1]: https://help.apple.com/xcode/mac/current/#/devbbdc5ce4f https://help.apple.com/xcode/mac/current/#/devbbdc5ce4f In theory an LLVM-based bitcode-like system could allow Apple to change CPUs and automatically recompile App Store binaries without developer intervention, but their current bitcode system does not support that.