Apple’s quarterly profit rocketed to a corporate record US$18 billion at the end of last year on booming sales of big-screen iPhone models, especially in China. The California tech titan also announced on Wednesday that it had sold its one billionth device powered by its iOS mobile operating system, on a day of dizzying figures – even by Apple’s high standards. And it said that its highly anticipated Apple Watch wearable devices, unveiled last year to fanfare, are on track to begin shipping in April. “We’d like to thank our customers for an incredible quarter which saw demand for Apple products soar to an all-time high,” declared chief executive Tim Cook. “Demand for iPhone has been staggering, shattering our expectation.” Demand for iPhone has been staggering, shattering our expectation Tim Cook Blockbuster sales of the recently released iPhone 6, in particular, are signs of huge pent-up demand for larger-screen smartphones, likely to boost sales throughout this year, according to Forrester analyst Frank Gillett. “I would expect the surge in China and elsewhere to hold for quite a while before it settles down,” Gillett said. “People have been waiting for an iPhone with a bigger screen and smartphones are only increasing in importance in our lives.” The record quarterly profit – on unprecedented revenue of US$74.6 billion – was driven by the sale of 74.5 million iPhones, well ahead of most analysts’ expectations. The staggering profit topped the US$15.9 billion made by ExxonMobil in the second quarter of 2012, according to Standard and Poor’s, to write Apple into the history books. As well as the larger screen iPhone 6 models, analysts credited a partnership with China Mobile as powering sales. Sales of iPhones doubled in Greater China, its number two smartphone market, according to chief financial officer Luca Maestri. Cook described the fevered excitement around the debut of iPhone 6 models in China as “phenomenal.” “We are a big believer in China,” Cook said. “It is an incredible market. I think people there love Apple products.” But it was not just China: iPhone sales leapt 44 per cent in the United States and doubled in Brazil. Sales of iPads dipped, but Apple set new records in the quarter for sales of Macintosh computers and revenue from digital goods bought from its App Store. Cook remained optimistic about the long-term potential for Apple’s iPad line. He noted that the ranks of first-time iPad buyers remain strong in China, Britain, the US and elsewhere and that the devices account for the bulk of online activity and shopping seen from tablets. “I believe that, over the arc of time, the iPad is a great business,” Cook said. “I am thinking over the long run.” Apple and others are still trying to tune into the rhythm of the market when it comes to how long people typically own tablets before replacing them. Cook also noted that large-screen iPhones might be nibbling at one edge of iPad sales and Macintosh computers at another edge. He was confident that an alliance between Apple and IBM announced last year will lead to iPads becoming more enticing for workplaces. Cook also said Apple is seeing rapid adoption of the Apple Pay mobile financial transactions system, which is synched to the latest generation of iPhone.