As Lee points out in a blog post, the Apple Watch's specs are well above those of a typical Windows 95 computer, so it makes sense that it should be capable of running the Microsoft's old OS. Of course, there are quite a few hurdles to get past first, including the fact that Apple doesn't exactly provide a way to install new operating systems on the Watch, let alone apps that it hasn't vetted.
IT TAKES A FEW HACKS TO GET THIS WORKING
To get 95 running, Lee had to modify Apple's development software in "rather unorthodox ways," he tells The Verge. That allowed him to essentially turn Windows 95 into a Watch app, which also emulates an environment for the OS to run on.
Lee also had to deal with the fact that the Apple Watch's screen really wants to turn off when it isn't in use. To deal with that, he set up a motorized tube that constantly turns the Watch's crown, preventing it from falling asleep.
The result is very slow, but impressively functional. Though it looks a bit like he's swiping around, Lee says that he altered the Watch's software to let Windows 95 track a single fingertip, allowing the mouse to be moved by tapping where he wants it to go.
For some reason, developers can't seem to resist taking classic games and apps and putting them on platforms that they were never meant to run on. Windows 95 is a pretty great example, but we also saw a Facebook developer put Doom on an Apple Watch.