Myles Jihme, a student from Malaysia, waiting outside the Apple store in Sydney said he intended to buy two iPads, the maximum allowed by Apple, and would auction one for charity. "All the profits from the sale will go to Japan's disaster fund," he said.

In addition to Friday's roll out, the iPad 2 will be available in China's Hong Kong, South Korea, Singapore and other regions and countries in April.

Apple now faces increased competition from rivals. Samsung Electronics and Motorola have tablets on the market and Blackberry-maker Research In Motion and Hewlett-Packard Co are set to release tablets in coming months.

Japan supply woes

Analysts are also concerned that Apple will face shortages of key components for the iPad 2 because of the earthquake and tsunami that struck Japan two weeks ago.

Several key components in the new version of Apple's popular iPad come from Japan, including the battery and the flash memory used to store music and video on the device, according to IT research house iSuppli .

Apple delayed sales of the iPad 2 in Japan, but has said that had nothing to do with any component shortages.

Analysts say it's too early to gauge the extent of component supply shortages, while the wait time on delivery of online orders has shortened to 3-4 weeks in recent days from as high as 6-7 weeks, suggesting component shortages have not reached critical levels.

"The quake will have an effect on supplies of the iPad, since some parts come from Japan," said Akira Minamikawa, Vice President at iSuppli in Tokyo.

"It's too early to say how far production will be affected. But there are a number of iPad parts manufacturers, including Toshiba and Hitachi for LCD panels, while Toshiba also makes flash memory."

In Taiwan, the CFO of TPK Holdings , a major supplier of touch screens to companies that include Apple, said it has had no problems with supplies because it has many secondary sources outside of Japan.

Hon Hai Precision Industry Co, a contract manufacturer and subsidiary of Foxconn that is heavily reliant on Apple's business, said it does not expect supply problems in the near-term.

Most of the Japanese factories that are thought to supply Apple with parts are situated well away from the earthquake-hit area, still distribution of supplies is expected to be hit by nationwide fuel shortages.

Apple's clout in the supply chain means investors remain confident -- for now -- that it enjoys priority and can secure critical components ahead of competing manufacturers.

Still, Apple is unlikely to avoid a hit from the disruption in Japan, analysts said. 

"We think the disruption especially for chemical materials could continue throughout Q2 and when the components become absent, it's inevitable that Apple would be affected," said Calvin Huang, an analyst at Daiwa in Hong Kong.

"Then we will see a situation that customers will have to wait for months for an iPad to arrive after placing an order."