Apple unveiled a third-generation iPad on Wednesday enhanced with features aimed at keeping it safely on the throne of the booming tablet computer market.

The new iPad boasts a powerful quad-core processor, eye-grabbing resolution on par with that of an iPhone 4S, and the ability to connect to the latest 4G LTE telecom networks that move data faster than their predecessors.

"We think that iPad is the poster child of the post-PC world," Apple chief executive Tim Cook said, noting that iPad sales topped those of any personal computer maker during the final three months of last year.

"We have redefined once again the category Apple created just two years ago with the original iPad," Cook said at a press event in San Francisco, the first major product release by Apple since the death of founder Steve Jobs.

The new iPad will go on sale March 16 in Canada, France, Germany and the United States at the same price as the previous models, which start at $499 for the most basic iPad featuring wireless connectivity only.

An iPad with 16 gigabytes of memory and with both Wi-Fi and 4G connectivity will cost $629 in the United States while a 32GB Wi-Fi/4G model will cost $729 and a 64GB version with Wi-Fi and 4G will cost $829.

In a bid to cater to budget-minded shoppers, Apple will sell a 16GB version of the iPad 2 at a trimmed price of $399.

The new iPad screen features 264 pixels per inch in what was billed as the best display ever on a mobile device.

"Images on it look stunning," Cook said of rich "retina display" resolution.

The new iPad also features a five-megapixel camera and high-definition video recording.

Apple marketing executive Philip Schiller said the latest model has the same 10-hour battery life as its predecessor, with the span cut by about an hour with constant use of high-performing 4G telecom networks.

The third-generation iPad weighs 1.4 pounds and is 9.4 mm thick, slightly heavier and slightly thicker than the previous model.

Apple showed off an enhanced suite of iPad applications for tasks ranging from movie editing to making music or managing one's life.

A new iPhoto application turns the iPad into a slick tool for editing pictures with simple touches or automated features.

Epic Games president Mike Capps joined Cook to show off a version of the Infinity Blade videogame for the iPad, contending the quality was comparable to videogame console play.

"It is an evolutionary upgrade with a lot of revolutionary features," Gartner analyst Michael Gartenberg told AFP. "It is going to put a lot more pressure than before on iPad competitors.

"The updates to GarageBand, iMovie, and the new iPhoto will drive this going forward," Gartenberg said.

"At the end of the day it isn't going to be Tim Cook that sells the iPad, it is going to be the iPad that sells the iPad; and they are going to sell a lot of them," he said.

Apple has dominated the tablet market since launching the iPad two years ago and few expect that to change anytime soon.

IMS Research said Wednesday that Apple is expected to increase its tablet market share to 70 percent in 2012 from 62 percent in 2011 and it will ship 70 million iPads this year, up 71 percent over the previous year.

"There is a large customer base loyal to Apple products that have been waiting for the latest tablet," IMS Research PC market analyst Gerry Xu said. "Many owners of the iPad 1 are also expected to upgrade to the latest release.

"To date there is no significant threat to the iPad's continued dominance in the tablet market," Xu said. "In fact, the share of Android tablets is forecast to fall from 35 percent in 2011 to 26 percent in 2012."

The California-based gadget-maker on Wednesday also released an updated version of the Apple TV box used to stream movies, television shows and other content from the Internet to high-definition TV sets.

The new Apple TV box, which Apple said features a streamlined new user interface, will sell for the same $99 price as the previous model.

Apple released the first version of Apple TV in 2007 but it has never really caught on with the public.