There's one piece of good news for Apple underneath weakening iPhone demand (AAPL)

Demand for Apple's priciest phone, the iPhone X, is rising, and it's the model in highest demand.
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Apple's has had a tough time growing its iPhone business, with sales growth effectively flatlining in recent quarters.

But in a spot of good news for Apple, demand for the company's priciest phone is rising, and is stronger than any other Apple phone.

UBS surveyed 7,000 consumers, and found that "some 44% expect to buy an iPhone X versus 30% in our October survey."

Plus models make up about 40% of the remaining demand outside of the iPhone X, according to UBS. That could bode well for Apple, as the Plus models are more expensive than the regular iPhone 6, 7, and 8. In other words, consumers are opting for the most expensive iPhones, whether it's the X or the Plus models .

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Milunovich raised his price target on Apple from $190 to $210, 11% above its current level, because he expects its services business to show strong growth. "We think the narrative is shifting from iPhone units to a consistent franchise with low single-digit hardware growth augmented by higher-margin, faster growing services," he wrote.

Apple is up 10.3% this year.