SAN FRANCISCO - A thin and smiling Apple chief executive Steve Jobs launched a much thinner, curved iPod Nano music player and joked about the state of his much-discussed health.

Kicking off a theatrical press event in San Francisco on Tuesday by poking fun at persistent rumours about his health, Mr Jobs stepped on stage in his trademark outfit of jeans and long-sleeved black shirt in front of a screen that flashed 'The reports of my death are greatly exaggerated' - a quotation borrowed from Mark Twain.

The 53-year-old had undergone successful surgery to remove a rare type of pancreatic cancer in 2004. But concerns about his health had re-emerged after he appeared gaunt at another product launch in June. Recently, Bloomberg News had also erroneously published a Jobs obituary.

On Tuesday, Mr Jobs looked thin but cheerful. 'Enough said; the real topic of today is music,' he began.

He went on to announce new products, including a slim new iPod Nano model that upgrades the technology while returning the gum stick shape people preferred. He also showed off an upgraded iPod Touch model slimmer than the original version and with a built-in speaker.

The redesigned iPod Nano comes with a "shake to shuffle" feature

The iPod lineup combines feature upgrades with price cuts of as much as US$100 (S$140) on higher-end models.

The curved aluminium-and-glass Nano - the best-selling iPod - will now be available for US$149 with 8GB of storage, US$50 less than the predecessor model. A 16GB version will cost US$199 and is capable of playing back 24 hours of music or four hours of video.

Mr Jobs also showed off a thinner, US$229 version of the Web-connected iPod Touch with rounded edges and 8GB of storage. At the high end, Apple is charging $399 for 32GB.

He cited statistics showing that iPods command nearly 74 per cent of the MP3 player market and said that more than 100 million applications for iPhones and iPod Touch models have been downloaded since the 'App Store' opened two months ago.

He also addressed concerns about iPhone 3G performance problems by saying that a free iPhone 2.1 update will be released tomorrow to fix the glitches.

'It's a big update,' the Apple CEO said of the iPhone software release. 'It fixes a lot of bugs.'

Apple has incorporated motion-sensing 'accelerometer' technology into the new Nano, which adjusts screens to how the devices are held and lets people shuffle music with 'a shake'.

'You just take your iPod, shake it and it's shuffled,' Mr Jobs said, flicking his wrist to demonstrate. -- Reuters, AFP