Apple's plan to add generative AI to its iPhones and revive sagging sales in the crucial Chinese market will be in focus on Thursday, when the tech giant is expected to report its biggest quarterly revenue decline in more than a year.

Long considered a must-own stock on Wall Street, Apple shares have underperformed other Big Tech companies in recent months, falling more than 10% this year as fears mount about its slow roll-out of artificial intelligence services and as a resurgent Huawei takes market share in China.

Analysts on average see iPhone sales, which account for about half of Apple's revenue, falling 10.4% in the first three months of 2024, according to LSEG. That drop would be the steepest in more than three years.

The year-ago iPhone revenue that the 10.4% iPhone sales drop is measured against was unusually high as Apple satisfied pent-up demand after the COVID pandemic, company executives previously noted.

At least $5 billion of the $51.3 billion in iPhone sales a year ago was essentially catching up from disruptions in the December 2022 quarter when COVID lockdowns in China hampered iPhone production, executives said.

Even with that factored in, Wall Street expects a slight decline in iPhone sales, and analysts estimate Apple's total revenue declined 5% in its fiscal second quarter ended in March. That would be Apple's biggest revenue decline since the December 2022 quarter, when revenue fell 5.5%.

Apple earlier this year lost the crown of the world's most valuable company to Microsoft. Its market value stands at $2.68 trillion after the share price declined 11.24% so far this year.

Weak revenue and falling shares have pressured Apple to spruce up its flagship device after years without major upgrades.

The company is in talks with OpenAI and Alphabet-owned Google to add genAI features for the iPhone that could be unveiled at what is expected to be its biggest-ever annual developer conference in June, Bloomberg News has reported.

Analysts believe such an AI integration could drive demand for the next iPhone series, expected to be announced in the fall.

While executives at Microsoft, Alphabet, Meta Platforms and other major technology firms have talked up their AI strategies on quarterly conference calls in recent months, Apple CEO Tim Cook has discussed his plans for the emerging technology much less.

Adding AI features to iPhones could also help Apple to compete better with Huawei and Samsung Electronics, which reclaimed the title of the world's top smartphone vendor from Apple this year, driven by demand for the AI features in its Galaxy S24 smartphones.

"Replacement cycle tailwinds and incremental generative AI features set up Apple well for a strong iPhone 16 cycle," Bernstein analyst Toni Sacconaghi said this week as he upgraded the company's shares to "outperform" from "market-perform."

"We believe prevailing weakness in China is more cyclical than structural, and note historically Apple's China business has exhibited much higher volatility than Apple overall, given its very feature-sensitive installed base."

Thursday's earnings will also be watched closely for updates on the company's stock buyback plan and the Vision Pro, Apple's first major product in years that hit the shelves in February.

After initial enthusiasm, there have been signs that demand slowed for the $3,500 device, with an analyst saying this month that Apple has pulled back its production estimates for the mixed-reality headset.

The rest of the company's hardware business is also reeling from soft demand, with iPads and Mac sales expected to fall 11.4% and 4.3%, respectively, in the March quarter.

Apple has signaled it is sharpening its focus on the devices, which have also been hobbled by a lack of major upgrades.

At an Apple event this month, a revamped iPad line-up is expected to be unveiled and media reports have said that it plans to update every Mac model with faster, AI-focused M4 processors.

The services business, which includes App Store and subscription services such as Apple TV, is expected to remain a bright spot with revenue growth of 7.7%.

Apple shares closed down 0.6% at $169.30 on Wednesday.

(Reporting by Yuvraj Malik in Bengaluru; Editing by Shounak Dasgupta and Richard Chang)