Ben Reitzes of Barclays has been bullish on Apple for the past 10 years, but that changed Thursday.
The senior technology analyst at Barclays Capital downgraded the tech company to equal weight after keeping an overweight rating on it for a decade, saying that he "agonized" over the move.
During an interview on "Squawk on the Street," Reitzes said he made the call because most of Apple's new product lines—such as a much-anticipated smartwatch—seem designed only to help sell more iPhones.
As the tech industry shifts its emphasis from hardware and operating systems to cloud-based computing and multiplatform software, he added, Apple will be hard-pressed to continue increasing iPhone sales past 10 percent.
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"The market is going to move toward more social, cloud and messaging-type services where there's a potential that the actual smartphone itself could get hollowed out a little bit, and the operating system maybe even becomes a little less important," Reitzes said.