Among the highlights: Apple showed off a simplified look on iPhones and iPads. It is the most radical design change since the iPhone made its debut in 2007. It's part of iOS 7, the new operating system for mobile devices.
The keynote kicked off at about 10 a.m. PDT. Apple's Worldwide Developers Conference goes through Friday.
Here's a running account of the event, presented in reverse chronological order. All times are PDT.
Presenters include CEO Tim Cook; Craig Federighi, senior vice president for software engineering; and Eddie Cue, senior vice president for Internet software and services.
Apple says iOS 7 will be available on the iPhone 4 and later, the iPad 2 and later and the iPad Mini. A test version is available to developers starting Monday. It will be available for everyone else this fall. That's when Apple is likely to introduce a new iPhone as well.
Apple unveils a streaming music service, iTunes Radio. It is built into iOS 7 and works on Apple's mobile devices. It will also work with Apple's iTunes software on Mac and Windows computers.
It's free with ads, though subscribers of Apple's iTunes Match service will get it ad-free. Availability will start in the U.S.
Apple unveils a feature for organizing photos you take on iPhones. Instead of the endless streams of the past, they will be organized into moments -- such as "home" or "trip to San Francisco." Federighi says that while you may not remember when you did something, the device's software does.
Apple also says its Siri virtual assistant will use search results from Microsoft's Bing -- furthering its avoidance of Google services. Last year, Apple unveiled its own Maps app to replace one using Google's mapping service.
The company also says it will come out with a version of iOS built into cars.
Apple takes a jab at one of its rivals, Samsung Electronics Co. The South Korean giant has been touting Android phones that let you share photos and other content by bumping phones together. Samsung phones have a near-field communication chip that iPhones lack.
Federighi says iOS 7 will let you share content wirelessly with a feature called AirDrop.
He says, "No need to wander around the room bumping your phone with others."
Apple shows off new features in iOS 7.
Apple demonstrates a new weather app with animation: It shows thunder when a thunderstorm is forecast, for instance. The calendar has been cleaned up and looks more streamlined. You can also get to your contacts list quickly while reading messages by swiping from the left of the screen.
Also coming to iOS 7: full multitasking. In the past, the ability to use multiple apps at once was limited.
You can also swipe up from the bottom to access a control center, for such functions as turning on the airplane mode and adjusting brightness. It's similar to a feature available at the top on rival devices running Android.
Apple's software will also figure out which apps you tend to use and make sure content is regularly updated for those.
Cook touts the advantages of Apple's iOS software for mobile devices and introduces a new version, iOS 7. He says it's the biggest change to the system since the iPhone's introduction in 2007.
Apple's design chief, Jonathan Ive, appears in a video showing a unified look that is applied across the system.
Icons in iOS now have a three-dimensional look that tries to mimic the real-world counterparts of certain apps. For instance, the icon for the Notes app looks like a yellow notepad and the Contacts app is represented by a leather-bound address book.
With iOS 7, Apple is favoring simplicity and consistency. Ive says Apple is introducing a new structure to bring order to complexity.
While design modifications could help Apple distinguish its devices from rival phones and tablets, they risk alienating longtime users. However, the audience cheered after seeing a video on the changes.
Apple unveils a long-overdue upgrade to its iWork suite of productivity software. The new version will tap Apple's iCloud online syncing service and will let you run the programs from a Web browser.
The current version dates back to 2009. The suite includes Pages for word processing and Numbers for spreadsheets. It's cheaper than Microsoft's Office, but has worked only on Apple devices. Because the new version works on a Web browser, you can now use it on a Windows computer, too.
Apple shows a video previewing an upcoming MacBook Pro. It promises faster connectivity through Thunderbolt 2 ports and better graphics performance.
It will be available later this year and will be assembled in the United States, consistent with Apple's previous pledge to move manufacturing of one of its existing lines of Mac computers to the U.S.
Apple announces new MacBook Airs with better battery life. The 11-inch model will have nine hours of battery life instead of five, while the 13-inch model will have 12 hours, instead of seven.
The new MacBook Airs start shipping Monday: The 11-inch one starting at $999 and the 13-inch model starting at $1,099. The Airs are thinner and lighter than traditional laptops.
Federighi says the maps team has been making improvements to the service, which had been panned when it came out last fall. You can search for directions on a Mac and have it sent to the iPhone, for instance. Apple will be competing with Google Maps, Microsoft's Bing and others on desktop and laptop computers. Apple's Maps app currently is available only on Apple's mobile devices.
The Mac is also getting the iBooks app previously available on iPhones and iPads. It's the latest evidence of Apple's software for mobile devices and traditional computers converging, although Apple has said it prefers to keep the two separate because the Mac software is designed for non-touch devices such as desktops and laptops.
The new Mac operating software will be out this fall.
Federighi unveils improvement in the Safari Web browser coming in the next version of Apple's Mac operating system. He demonstrates Apple's power-saving technology while browsing and announces one-click bookmarking. There's also an infinite scrolling feature -- when you get to the end of an article, it will simply go to the next one as you scroll downward.
Need help remembering all your website passwords? Apple has a new feature on its iCloud file-storage service. It will keep track of all your passwords -- encrypted for security -- across your various devices.
And when you're shopping, it will automatically suggest credit card numbers you've used in the past. You will still have to enter the security code on the back of your card, though.
Apple has had a practice of naming Mac operating system updates after cats. But Federighi worries that the company is running out of names. After joking that Apple will call the next one Sea Lion, Federighi says the next will actually be called Mavericks, a reference to a big wave area in the San Francisco area.
The new operating system will support tagging to help you find files more easily. Simply assign one or more tags such as "important" or "movies" to a particular document as you save it.
Mavericks will also work with multiple monitors, with docks and menus going across the various display screens. TVs connected via Apple's AirPlay can serve as one of those displays.
The new system also promises better battery life.
Cook opens the keynote by talking about the status of Apple's more than 400 retail stores worldwide. He says Apple's newest store is in Berlin, at a century-old building that was one of the city's first theaters.
He also touts Apple's online store and says the company has 900,000 apps there, including 375,000 specifically designed for the iPad and its larger screen compared with the iPhone.
Cooks walks on stage to applause from an audience of software developers and other Apple fans.
Copyright 2013 The Associated Press.