Apple is a big company. Even the littlest of changes they make are made bigger simply as a function of their size. So when they kick off their year with a keynote so packed that Tim Cook couldn’t even mention retail store stats, it’s huge.

It’s awfully tempting to break this down into subsections of OS X Yosemite and iOS 8 and discuss each individually. But, if it wasn’t clear before that Apple considers these two operating systems to be intertwined, it absolutely could not be any clearer now. The features that received some of the most pronounced applause were those that allowed for near-seamless transitions between iOS devices and your Mac. You can take calls and reply to SMS messages (not just iMessages) on your Mac, and enable a hotspot from your Mac without having to touch your iPhone. AirDrop now works between iOS devices and Macs, and there’s a sweet new technology called Handoff that allows for seamless workflows between equivalent Mac and iOS apps that support it.

Even the stuff that felt like it was contained to one platform was designed to make the two operating systems feel even more like two parts of the same story. The significant user interface overhaul in Yosemite is, by and large, borrowed from and related to iOS 7. The translucency, bright colours, simplified icons, and Helvetica Neue are by-the-book iOS, as is the near-identical Notification Centre. But, make no mistake, this is still a Macintosh, running the same powerful apps you’ve always expected. It still has Terminal, and it’s still based on Unix.

Some feature pairity went the other way, too, from OS X to iOS. Most noticeably, iOS is a hell of a lot more open to third-party developers than ever before. Different apps can now share data, which should make photo editing even better. Developers can add buttons to the system share sheet, too, so Instapaper, for example, could now be available everywhere, instead of just in apps that feel like supporting it. Finally, third parties can now add widgets to the Notification Centre on both iOS and OS X.

But, while these operating systems seem like they’re on an inevitable collision course, I doubt they actually are. They may now look similar and have even greater shared functionality, but they are still their own beasts. The easiest comparison is against Windows, where the same UI is used on smartphones, tablets, and the desktop. That’s not happening here. iOS is still designed for touch (aside from the persistent “×” buttons in Notification Centre), while OS X is still very much designed for a keyboard and mouse. They are siblings, but they are not twins.

I’ve said a couple of times previously that Apple has been taking steps to reorientate themselves for their future. Tim Cook shuffled up the executive team, bought companies small and large, and ushered the company through a series of significant transitions. It has felt a little slow at times, and it has been a little bit messy, but the fruits of that are beginning to appear. Today’s WWDC offered an astonishing glimpse at the future of the Mac, the iPhone, and the iPad. I’m looking forward to spending the next few months trying to better understand all that I have seen today.