Apple on Monday said iPhone 4 sales topped 1.7 million units for the first three days the device was available to customers.
Apple CEO Steve Jobs said the iPhone 4, which hit retail outlets Thursday, was "the most successful product launch in Apple's history" and apologized to customers who were turned away because there weren't enough iPhone 4s to go around.
The iPhone 4 launch hasn't been without its difficulties for Apple. As soon as the device became available, users began complaining about problems with the antenna.
Customers were easily able to demonstrate signal loss on the iPhone 4, essentially going from four bars to none, because of the way the device is being held. Apple responded to the complaints, suggesting that users not cover the antenna with their hand.
Some observers have been speculating that the issue could be software-related and that a fix from Apple could come as early as Monday with an update to iOS 4.