Apple (AAPL) unveils iPad Air 2, iPad Mini 3, and Retina iMac

Apple unveiled a new lineup of products Thursday. Apple revealed a new iPad Air 2 and iPad Mini 3, an iMac with a Retina display, and the release date of OS X Yosemite.

A month after it unveiled its new generation of iPhones, Apple was back onstage Thursday with new devices and big announcements. Let's walk through the biggest takeaways.

iPad

At the event, Apple revealed the iPad Air 2 and iPad Mini 3, the newest versions of its tablet device. The new version of the iPad Air 2 looks like the original Air, but it's 18 percent thinner. The iPad Air 2 has Touch ID, an A8X processor, and Retina display. The new iPad has an anti-reflective coating on the glass and an ultra-high resolution screen that is better than an HDTV.

"It makes the graphics feel like they are on top of what you're touching," Phil Schiller, Apple's senior vice president of marketing, said at the event. 

The new A8X chip is an improved version of the A8 chip that is in the iPhone 6 and 6 Plus, and it is 40 percent faster than the A7 chip in the previous iPad. The new iPad Air 2 will have a 10-hour battery life.

Mr. Schiller, who presented the new iPads, didn't speak much on the new iPad Mini 3. But he did say it will have Touch ID and will use the older A7 chip. 

The iPad Air 2 and Mini 3 will be available in the traditional silver or space gray, as well as a new gold-colored version. The iPad Air 2 starts at $499 and the iPad Mini 3 starts at $399. Pre-orders begin Thursday and will be shipped next week. 

iMacs

Apple unveiled the long-anticipated iMac with Retina display. The new Retina "5K" display has 14.7 million pixels, 47 percent more than ultra-HD 4K screens. "You've never seen a desktop with this level of display," Schiller said. 

Even with the ultra-high resolution screen, the new iMacs will only be 5 mm thick at the edges and 30 percent more energy efficient than previous models. The base model of the new iMacs will have a 3.5 GHz Intel i5 processor and Radeon R9 M290X graphics card, 8 GB of RAM, and a 1 TB Fusion drive. But customers can upgrade to a version with a 4 GHz Core i7 processor, 32 GB of RAM, a 3 TB Fusion drive or a 1 TB solid-state drive.

The new iMac with Retina display is only available in the 27-inch version. But Apple will continue to sell a 21.5-inch and 27-inch version without Retina display. 

Mac Mini, Yosemite, and Apple Pay

A new, upgraded version of Mac Mini was also released. It has a faster processor, Intel Iris graphics, and Thunderbolt 2. The new version of the Mac Mini is $499.

Along with the new devices, Apple's event outlined when some of the products it has already announced will be launched. The new operating system OS X Yosemite will be available free of charge starting Thursday. Yosemite updates the Mail, Spotlight, and Safari apps, and adds a cloud-syncing service called iCloud Drive, which allows users to upload and share data. 

Apple Pay, a new mobile payment system, and iOS 8.1 will both launch on Oct. 20.  

With all the new devices and software that Apple has unveiled in the past few months, there is one common thread between them all. At the event, Apple talked a lot about continuity, or the ability of these systems to seamlessly work together, from the Apple Watch to iPhone to Mac Mini.

"They're designed to be incredible products individually, but they're also designed to work together seamlessly," said Apple chief executive Tim Cook.

Using iCloud and Bluetooth technology, Yosemite and iOS 8 will allow users to begin a project on an iPhone and then continue the project on an iMac or an iPad. Apple will also be expanding AirDrop to easily send files from different devices.

"This is an incredible lineup of products and the ecosystem that supports them is something only Apple can create," Mr. Cook said. "This is our version of personal technology, and it has just started."