No, iOS is a lot of custom code, but it's also a lot of reusing open source, and a jnix kernel, and POSIX, and the thr same instruction set as many others.

It's just a skin on top of the same old stuff everyone else uses, but with more control so you can't reach underneath to see much of the foundation.

That said, it's a fairly deep skin by this point, and getting deeper, but compared to the whole depth of the stack we're talking about, it's still just the skin.

I think this is a matter of perspective. I think Mac OS is just about as innovative on Unix as Linux is. Not in exactly the same ways mind you but definitely they’ve invested more than just wrapping a shell around POSIX.

Keep in mind the original post was going so far as to talk about a having different protocol stacks (not TCP/IP), different display protocols, and different IO ports (Apple devices do have some of the latter). And if JPEGs aren't supported through libjpeg, we're actually talking about a completely different computing paradigm, so it's not even a von Neumann architecture. In the fact of that staggering amount of difference, the slight difference iOS and current MacOS have from Linux and Windows is very shallow. That for many things you can easily throw a compiler on there and compile the same open source project and it will link to the already existing libraries it needs, the same ones it will find on other platforms, shows this.

While I don't know enough to comment authoritatively on it, I think with respect to this Apple might have taken a step backwards (at least with respect to percentage of system that is unique, if not in total amount of libraries and code) when it switched to OS X. OS 9 and its prior versions were an entirely unique and custom OS designed at Apple. The whole switch to OS X was taking a UNIX core for stability and building on top of it.

Apple systems are quite different than the norm in many respects, but the scope of this discussion is so large that there's really little they do that's different than everyone else from that perspective, because nobody does anything different. It's hard to start from scratch and ignore approximately 80 years of concerted computer science effort and come up with something useful and usable in any sort of time frame that makes it worthwhile.

What it is is irrelevant. How it presents itself to the user is exactly as a holistic, integrated, carefully designed computing ecosystem.

I’m a software engineer, I’m perfectly well aware iOS and MacOS run on top of a Unix kernel. But unless I go looking for it, they will never shove this in my face and make it my problem.

Meanwhile, I’m still dealing with Linux-loving colleagues who cannot get their sound or webcam to work reliably and consider this an acceptable state of affairs.

> Meanwhile, I’m still dealing with Linux-loving colleagues who cannot get their sound or webcam to work reliably and consider this an acceptable state of affairs.

That's largely the fault of manufacturers who refuse to properly document their devices and release functional drivers. I don't think anyone considers that an acceptable state of affairs, merely tolerable if it allows using an open software stack that you can freely modify.

It's the fault of the Linux kernel, which insists against all evidence that drivers aren't valuable IP that costs a lot of money to develop and that it should all be GPLd, meaning the manufacturers don't bother writing them for Linux.

> Meanwhile, I’m still dealing with Linux-loving colleagues who cannot get their sound or webcam to work reliably and consider this an acceptable state of affairs.

This isn't so much of an issue anymore in my experience. Older webcams and sound cards that work flawlessly with Linux often don't work with newer Windows versions, though.

This is the difference between Product & Technology, in their literal terms