Apple sold more than 1.7 million iPhone 4s between 24th and 26th June according to figures released by the company.
Boss Steve Jobs described it as "the most successful product launch in Apple's history", although he apologised "to those customers who were turned away because we did not have enough supply".
In recent days Jobs has been less apologetic about a design quirk that means holding the phone a certain way can reduce carrier signal strength.
The phone's antenna array relies on a metal band around its circumference - something Jobs described as "brilliant engineering" at the phone's unveiling.
However, it seems that if you cover the area at the bottom left of the phone with your hand it reduces signal and even drops calls.
Apple's official advice was to "avoid gripping it in the lower left corner in a way that covers both sides of the black strip in the metal band".
The iPhone 4 is the "thinnest smartphone on the planet" according to Apple, and boasts a new screen with increased pixel density, improved battery life thanks to the iPad's A4 processor, and a gyroscope for "full pitch/roll/yaw sensing in 3D space", which Jobs has said is "perfect for gaming".
It also has a Wi-Fi only video call feature called Skype. Sorry, FaceTime.
In the UK iPhone 4 costs £499 for the 16GB version and £599 for the 32GB version, although availability is still limited i.e. we couldn't buy one at the Apple Store in Brighton yesterday.
Earlier this month Apple said that it had sold three million of its new iPad tablets in just 80 days of the device being on sale.