Jobs said that the iPhone, which comes with touch-screen controls and combines features from the iPod music player, will be available with four gigabytes of flash memory and sell for $499, and with eight gigabytes of flash memory for $599.
The set-top box, a revolutionary product in the transfer of digital files to television screens, will be available next month.
Jobs said the company will begin taking orders on Tuesday for the $299 video box, called Apple TV.
Jobs told the crowds at the event: "Every once in a while a revolutionary product comes along that changes everything. It's very fortunate if you can work on just one of these in your career. ... Apple's been very fortunate in that it's introduced a few of these."
Describing the patented touch-screen technology Apple is calling "multi-touch", Jobs said: "We're going to use a pointing device that we're all born with. It works like magic. ... It's far more accurate than any touch display ever shipped. It ignores unintended touches. It's super smart."
The phone automatically synchs your media - films, music, photos - through Apple's iTunes digital content store. The device also synchs email content, web bookmarks and nearly any type of digital content stored on your computer.
"It's just like an iPod - charge and synch," Jobs said.
iPhone is less than 1.25cm thick - less than almost any phone on the market today. It comes with a two-megapixel digital camera built into the back, as well as a slot for headphones and a SIM card.
The set-top box is designed to bridge computers and television sets so users can more easily watch their downloaded films on a big screen.
A prototype of the gadget was displayed by Jobs in September when Apple announced that it would sell TV programmes and films through its iTunes online store.
The product could be as revolutionary to digital movies as Apple's iPod music player was to digital music. Both devices liberate media from the computer, allowing people to enjoy digital files without being chained to a desktop or laptop.
Jobs told the crowd at San Francisco's Moscone Centre: "It's really, really easy to use. It's got the processing horsepower to do the kinds of things we like to do."
Apple TV will come with a 40-gigabyte hard drive that stores up to 50 hours of video. It features an Intel microprocessor and can handle videos, photos and music streamed from up to five computers within the wireless range.
Catapulting the company into the top ranks of music sellers worldwide, Apple, which sells 58 songs a second, or five million songs a day, sells more songs than Amazon.com and ranks behind only Wal-Mart, Best Buy and Target as a music retailer.
"We couldn't be happier with the growth rate of iTunes," Jobs said. He said Apple will sell digital films from Paramount. Apple has partnered Disney for several months, offering about 100 films on iTunes.
With Paramount's selection, it will have 250 titles available for download. With Tuesday's launches, it remains to be seen whether the leading seller of digital music players can colonise an entirely new category of gadgets.