If I write my Windows, Mac, Linux & Android code to utilise IPP, how can I then port those apps to iOS if it's not a not supported platform?
Are there any "swap-in" alternatives or is it possible to get IPP working on iOS?
Many ipp functions are just vectorized loops. Maybe you can rewrite them with https://ispc.github.io/ that supports ARM.
Intel IPP library supports Android. Here is the system requirements of IPP https://software.intel.com/en-us/articles/intel-integrated-performance-primitives-intel-ipp-2018-sys.... The instruction set needs to be compatible to run IPP on none-supported OSes.
For more complete information about compiler optimizations, see our Optimization Notice.