​Apple Inc. reports after the closing of stock market trading on Tuesday with much of the attention likely to be focused once again on the future of the company's key product, the iPhone.

According to Bloomberg, analysts' consensus forecast for adjusted earnings per share for the quarter stood at $2.16 US. The consensus revenue forecast for the quarter is $52.31 billion US.

Gene Munster of Loup Ventures said in a note that they expect iPhone sales for the third quarter will come in at 41.6 million units, roughly inline with the market's overall expectation of sales of 42 million.

"This implies three per cent year-over-year growth," Munster said.

The market will also be looking carefully to what Apple projects for the fourth quarter that concludes at the end of September, amid speculation the company could soon unveil some new iPhone models. The company has usually announced iPhone lineup changes during the last quarter of its fiscal year.

Munster said they expect the midpoint of the company's guidance for the fourth quarter will be one to two per cent ahead of the Street's forecast.

"If the talk of three new iPhones this fall (one refresh of the iPhone X, one 25 per cent larger model and one lower-priced LCD model) is accurate, the Street's one per cent [fourth-quarter] iPhone unit growth does not properly reflect that," Munster wrote.

Loup Ventures also sees growth of the company's services division of 19 per cent, just ahead of the market's forecast for 18 per cent growth.

A side story to the Apple earnings release will be the stock market reaction. A positive earnings report and outlook could send the stock higher, and possibly make Apple the first company with a market cap in excess of $1 trillion US.

In Monday trading, Apple's stock lost just under 0.6 per cent to close at $189.91 US, giving it an overall market capitalization of about $933.43 billion US.

Apple's earnings report will come after a tough day for the so-called FAANG (Facebook, Amazon, Apple, Netflix, and Google parent Alphabet) stocks after last week's big sell-off in Facebook shares. Netflix shares lost about 5.7 per cent on Monday, while Facebook was down by 2.2 per cent. Amazon slipped by 2.1 per cent, while Alphabet lost 1.8 per cent.

"When you see the market leaders pull back it's going to weigh on the entire market. We're starting to see profit taking in a lot of these tech companies and investors are getting out of growth stocks," said Shawn Cruz, manager, trader strategy at TD Ameritrade in Chicago.

"Since Apple is the last FAANG stock we are going to hear from, I think we need a really good report or we are going to see weakness in the market," he told Reuters.