Analyst firm Canalys says that Apple shipped around 4.2 million Apple Watches during the second quarter. Other analysts have similar projections: they believe the company shipped between 2.85 million and 5.7 million of the devices. That is much better than any other smartwatch did, but it falls far short of the numbers Apple would need to hit the 30 million in yearly sales that some analysts forecasted before the device's release.
Over the weekend, The New York Times speculated that the Apple Watch wasn't doing as well as expected because major mobile development firms hadn't yet released apps for the device. It pointed to the lack of apps by Facebook, Snapchat and Google as proof of its point.
On the other hand, other reports have found that 97 percent of Apple Watch buyers are satisfied with their purchases.
Apple will report its quarterly earnings on Tuesday and may release more information about Apple Watch sales then.