Apple already working on next release?

Apple's iPhone X may have only been on sale for a few days, but Apple's plans for its successor are already being analysed.

Experts believe the tech giant will release two iPhones next year - one an updated X, and one an "XL" with the same design, but a larger screen.

KGI Securities' analyst Ming-Chi Kuo says Apple will launch not one but two iPhones with OLED displays and stainless steel cases, according to Daily Mail.

The new report also predicts Apple will make changes to the stainless steel metal frame to improve data transmission quality.

Apple's current flagship iPhone lineup includes three models with only one OLED option: the 4.7-inch iPhone 8 and 5.5-inch iPhone 8 Plus with LCD screens, and the 5.8-inch iPhone X with OLED.

The second model referenced in KGI's report may be a larger 'Plus' version of the next iPhone X, 9to5Mac believes.

Face ID is also expected to come to new iPad Pros.

Apple shares rose to a record high on Friday as more analysts set a trillion-dollar valuation on the company, following a blowout fourth quarter and an upbeat forecast that quashed investor concerns around the iPhone X.

The stock rose as much as 3.7 per cent to $174.26, briefly breaching US$900 billion ($1.3 trillion) in market value, amid declines in the broader market.

The gains added nearly US$32b ($46.1b) to the company's market capitalisation.

The Cupertino, California-based company also forecast a strong holiday quarter ahead, which will include the iPhone X that started selling on November 3.

"We see iPhone X unlocking pent-up iPhone upgrades, especially in China, driving more than 20 per cent iPhone unit growth and a revenue and earnings beat in 2018," analyst Katy Huberty on Morgan Stanley said.

The glass-and-steel US$999 phone appeared to have brought back the frenzy associated with iPhone launches - long lines formed outside Apple stores across the world as fans flocked to buy the new phone.

The company will make 30 million iPhone X units during the current quarter, Nomura Instinet analysts estimated, allaying production worries related to the phone.

IPhone X's launch follows weeks of concerns among analysts about the production of the phone, which for the first time includes new facial identification software to replace the fingerprint used on previous phones.

Apple said on Thursday it expects first-quarter revenue of US$84b ($121b) to US$87b ($125b), at the high end of analysts' average expectation of US$84.18b (121.4b), according to Thomson Reuters I/B/E/S.

"We - and many others - had feared that guidance could be weaker, reflecting only 9 weeks of the flagship iPhone X and limitations on supply," Bernstein analyst Toni Sacconaghi said.

At least 13 brokerages raised their price targets on the stock, with Citigroup making the most bullish move by raising its price target by $30 to $200.

Of the 37 analysts that track the stock, as per Thomson Reuters data, 31 had a "buy", or higher rating. None had a "sell".

Drexel Hamilton's Brian White is still the most bullish among Apple analysts tracked by Thomson Reuters, raising his target price further to $235.

Apple's fourth-quarter results underscored the company's ability to drive growth not just on iPhones, but across its range of products, analysts said.

The company's suite now includes five different iPhone models, the iPad, the Mac and the Apple Watch as well as its fast-growing services.

Apple said it sold 46.7 million iPhones in the fourth quarter ended September 30, above analysts' estimates of 46.4 million, according to financial data and analytics firm FactSet.

Mac and iPad sales too were above the estimates of most analysts.