SHANGHAI (AFP) - Apple began selling its latest iPhone in China on Friday, nearly a month after other major territories due to a licence delay by regulators, but it faces a tough battle with rivals led by Samsung in the crucial market.

Staff at an Apple Store in downtown Shanghai clapped and congratulated iPhone 6 customers as they left the shop, which opened two hours early for those who had pre-ordered.

The iPhone 6 with 16GB of memory is selling for the equivalent of US$867 (S$1,104) in China, significantly higher than neighbouring Hong Kong where the same model retails for $726.

The top-end iPhone 6 Plus with 128 GB sells for US$1,277 (S$1,626) in the mainland.

The new gadget hits shelves in China a day after the tech giant unveiled a new line-up of iPads in the United States in a bid to face off tough competition in the cooling tablet market.

Apple's products enjoy a devoted following in China, the world's second-largest economy and the largest smartphone market according to an industry estimate.

It launched the large-screen iPhone 6 and iPhone 6 Plus in 10 countries and regions on Sept 19, but could not do so in mainland China because it lacked a key network access licence.

Customer deliveries began Friday in the company's 12 retail stores in mainland China, and through the country's three major telecom providers and other sales channels.

E-commerce firm JD.com said it had taken 9.5 million pre-orders for the iPhone 6 and iPhone 6 Plus as of Thursday.

But Apple is only in sixth place in China's highly fragmented smartphone market, where cheaper phones using the Android operating system are popular.

Apple has a 6.9 per cent share, according to consultancy Analysys International, far behind leader Samsung of South Korea, which has 15.4 per cent.

Analysts said the new models' larger screen would appeal to Chinese consumers and the launch should help Apple's sales, despite their high prices.