In A Latest Move Apple Has Decided To Open Source It’s iOS And macOS Kernel Source Code For ARM Chips.
As a part of it’s open source adoptation policy, Apple releases a small bit of Darwin code every year. Apple has always shared the kernel of macOS after each major release. Despite of being open source, it was however not compatible with ARM based Chips. Meanwhile, Apple has now decided to open source it’s code for ARM based Chips too.
However, this is just the kernel, nothing more than that. You won’t get chance to build your own apple kinda device and more. But it can be big help for developer to learn about the various structure of iOS kernel and it’s mechanism.