Apple is set to unveil new iPhones, aiming to gain fresh momentum in the premium segment of a global smartphone market showing signs of fatigue. In its usual secretive style, Apple has remained mum about revelations planned for Wednesday's event at its spaceship campus in Silicon Valley, but the timing fits its pattern of annually introducing new iPhone models. Speculation includes talk that Apple will introduce three new iPhone models, infusing some with features from a premium iPhone X that debuted last year with a $1,000 price tag. While the iPhone has made Apple the world's most valuable company worth more than $1 trillion, it has slipped to third place among smartphone makers as Chinese-based Huawei has grabbed the number two spot. Still, analysts say Apple has a formula that works with a loyal customer base and steady sales.

"There is nothing in their product line-up that isn't working for them in the premium segment of the market, so there is no imperative for them to break that mold," NPD analyst Stephen Baker said of Apple likely sticking with modest improvements in new iPhones this year.

"They gobble up most of the profits. I don't think they are under any pressure at all."

Technalysis Research chief analyst Bob O'Donnell agreed that Apple is fine with holding its niche in the market.

"Apple doesn't have to prove anything, other than that they are willing to segment the market more," he said, while pointing out that the company will likely be "offering a wider array of choices."

Samsung, the world's biggest smartphone maker, last month unveiled its latest flagship handset, the Galaxy Note 9, and next month Apple rival Google will hold an event at which it is likely to showcase new Android-powered top-end Pixel phones. Apple is also expected to introduce a lower priced iPhone with some X features but a less expensive LCD screen.

The event may also include Apple Watch internet-connected wrist wear getting its first significant redesign since it debuted three years ago. While Apple watchers wait for the company to wow the world with a surprise such as augmented reality glasses or an Apple car that drives itself, the company has ramped up the amount of money it makes selling online services and digital content to the vast sea of iPhone users.