Apple chief Tim Cook personally kicked off sales of the iPhone 6, joining in "selfies" and shaking hands with customers Friday outside the company's store near his Silicon Valley home.
Cook was dressed in a black T-shirt and jeans as he worked his way from one end to the other of the long queue outside the Apple Store in the city of Palo Alto shortly before it opened.
"I want to share in the excitement," he said in response to a question from one of the reporters tagging along as Cook welcomed devotees who made the pilgrimage to get Apple's new big-screen smartphones on launch day.
When asked by to pose for a picture with a fan, Cook quipped "Sure, as long as it's with an iPhone."
Cook said that he has had both an iPhone 6 and an iPhone 6 Plus for months in what is "a privilege of being at Apple."
He took part in a clapping count-down inside the window-walled shop before swinging open a glass front door to let iPhone 6 buying there commence.
Cook's local Apple Store was among the last to join in an iPhone 6 roll-out that began many time zones away in Australia.
Television news footage from Australia showed a man identified as the first iPhone 6 buyer drop his new purchase while fumbling it out of packaging to show a reporter.
Buyers from China, deprived of the latest iPhone launch at home, were Friday among the first in line in Japan to grab the "6" and its new large-screen cousin as Apple hit back at rivals.
Licensing problems in China meant the global rollout went ahead without the huge and lucrative market, in a blow to Apple which had trumpeted its inclusion in the initial wave of the last iPhone launch.
Both new iPhones have larger screens in what some consider Apple catching up with the "phablet" trend pioneered by competitors.
The iPhone 6 has a screen of 4.7 inches and the 6 Plus is 5.5 inches, reflecting a growing preference for bigger displays, despite Apple's earlier vow to stick with the traditional size.
Main rival Samsung has long had a range of larger handsets, which are popular in Asia, and will soon release a new Galaxy Note 4 phablet.
Apple says more than four million pre-orders were received in the 24 hours after the sale was announced.
Other markets launched Friday are Singapore, Britain, France, Germany, the United States, Canada and Puerto Rico. Some 20 more countries will get the new iPhone from September 26.