Thousands of Apple fans around the world camped out overnight to be among the first to get their hands on the new iPhone 6S range.

However, some queues were notably smaller than last year, with an estimated 400 people in London compared with 1,000 last year.

Apple expects its first-weekend sales of the phones to exceed last year’s debut of 10 million units on the back of “very strong” preorders, while some analysts predict that it could sell as many as 12 million by tomorrow. “Customer response to iPhone 6S and iPhone 6S Plus has been extremely positive and preorders this weekend were very strong around the world,” a spokesperson for Apple said.

Apple has declined to state exactly how many preorders it has received, however.

The iPhone 6S and 6S Plus feature a “3D Touch” screen, upgraded camera and faster processor. The product launched on Friday in Australia, Canada, China, France, Germany, Hong Kong, Japan, New Zealand, Puerto Rico, Singapore, the UK and the US.

But some investors are concerned that Apple might struggle to increase its sales after a bumper year. Shares in the group fell nearly 22 per cent between mid-July and late August over worries about the iPhone’s growth outlook amid economic uncertainty in China.

Daniel Ives, analyst at FBR, said Wall Street was looking for sales of 12 million units.

The iPhone’s strong momentum in the past year has increased its share of the market, squeezing out smaller players such as BlackBerry and Windows Phone.

Analyst group eMarketer estimates that 43 per cent of smartphones sold in the US will be iPhones this year, up from 40 per cent in 2013, while in the UK Apple has 32 per cent of the market. – The Financial Times Limited