By Joanna Stern

You can't eat a computer.

That's what my 2-year-old said to me this morning, right before I holed up in my home office to watch the video stream of Apple's annual developers conference. He was confused as to why I was going to be writing about 'apple' today instead of eating one.

He's right, of course, but that doesn't mean the fruit company from Cupertino didn't give us lots to chew on today.

Let's see here: With iOS 14, the iPhone's new widgets will give you more information in just a glance. With an AirPod Pro software update, those little ear computers will render movie-theater sound that stays centered as you move your head. With WatchOS 7, your wearable will sense when you're washing your hands -- and make sure you go a full 20 seconds. And with MacOS Big Sur, laptops might finally get battery life to outlast a New York-to-Shanghai flight (presuming we can ever take one of those again).

Apple may not have packed the tech press and software developers into a theater Monday to hear its fall software updates, but it packed hundreds of features into a two-hour presentation. It mapped out an exciting -- yet confusing -- world where its various devices overlap more than ever in both aesthetics and functionality. Here's a breakdown of the biggest announcements.

iOS 14

In a year when cash-strapped shoppers might avoid shelling out $700 or more for a new iPhone, iOS 14 stands to make many very happy. It's available to all iPhones that currently run iOS 13, going back to the iPhone 6S. And it's got the biggest overhaul to the home screen and interface, well, possibly ever. And not in a scary "Who moved my cheese?" sort of way.

There's a new feature called App Library, which will group your apps by category so you don't have to make your own folders or flip through pages and pages of icons. You can also add widgets to your home screen so you don't have to launch an app to check the temperature or your next meeting. Can you say, "Thank you, Android"? Google's mobile OS has had this ability for years. These widgets will also be available in iPadOS and the new MacOS Big Sur.

The software is jam-packed with other features, too. If you're like me and spend your days trying to make sense of your family's big group message chain, you'll now be able to reply to specific messages inline. You can also pin your most important chats at the top of the app.

Then there is a new tool that promises live translation of different languages. (We'll have to test that to really see how well it works.) Plus, get ready to see App Clips in the world. This new breed of mini apps can be triggered by web links, QR codes or even wireless transmitters, so that you don't have to hunt through the App Store for a specific app to pay for your parking spot or order a coffee.

Speaking of the App Store, I'm very happy to see Apple adding new privacy "nutrition labels" to app listings. Now before you even download an app you'll be able to find out if it will require access to your location, contact info, ad identifiers, etc. I had written about the need for such a feature last year.

WatchOS 7

For years, lots of cheap wearables have been able to track your shut-eye. Finally, so can Apple Watch. When you wake up, you will get a detailed breakdown of your sleep, plus a reminder to charge up your watch before heading out.

The other big health-related watch feature? A hand-washing timer. Using internal sensors including the microphone, the watch will automatically detect when you are about to scrub up (yes, it listens for the suds) and start a countdown, nagging you if you stop early.

I look forward to testing this out, but I've gotten quite good at singing the ABCs.

Besides, I had been hoping to hear more about other Covid-19-related health features. Perhaps something even more helpful, like a pulse oximeter, will come with this fall's Apple Watch hardware update.

iPadOS 14

The iPadOS 14 didn't get as many new features as in years past but Apple did fix some longtime problems, and continue to make the iPad a "computer." For instance, an incoming call will no longer take over the whole screen -- you'll just see a notification along the top of the screen. (This feature will also come to iPhones with iOS 14.)

If you really want to start to understand the difference between an iPad and a Mac (and an iPhone), the answer seems to be in the Apple Pencil. The stylus has a new feature similar to one found on Windows Surface tablets: Instead of switching between writing and typing, you will now be able to handwrite into text fields and your scribble will be transcribed into text.

MacOS Big Sur

The Mac operating system is getting a full visual overhaul to make it look much more like iOS and iPadOS -- think rounded app icons, a messaging app that doesn't look like it's from 2010 and a settings panel, accessible from anywhere, that looks like your iPhone's Control Center.

The biggest news is that Apple will be moving its Macs from Intel processors to its own Apple silicon. (My colleague Nicole Nguyen has all your big questions about this answered here.)

What will that mean for you? Well, that your future Mac will be a lot more like your iPhone or iPad. That is, the battery life should be longer and the performance should be peppier. Plus, it will have the ability to run iPhone and iPad apps natively on the Mac.

It is one of the most exciting things to happen to the Mac in years. It's also going to be one of the most confusing, as the lines blur between iPads and Macs. They're all computers. Don't try to eat them.

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Write to Joanna Stern at joanna.stern@wsj.com