New rumors about a second generation Apple Watch could lead to slower sales of the first version of the high-end wearable device, according to one analyst.
Apple Watch sales have already slowed since an estimated 1 million units were sold in its first weekend, S&P Capital IQ analyst Angelo Zino said in an interview with CNBC. Sales may pick up before the holiday season, but that increase may still disappoint, he said.
Consumers could be holding out for an upgraded version of the device, Zino said. He expects a second version to launch sometime next year.
Read MoreApple Watch 2 will have video camera: Report
The second iteration is expected to have a FaceTime camera and greater independence from the iPhone, according to a report from 9to5Mac, citing anonymous sources.
But the watch isn't expected to have longer battery life, according to the report. Its battery charge, which Apple says should last up to 18 hours, is the Watch's biggest drawback, Zino said.
Apple declined to comment about the report.
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Having an HD video camera on the device is good news, and a logical next step, Zino said. Early versions of Samsung's Galaxy Gear smartwatches came with a video camera, but later versions did not.
