iPhone 4 will be available June 24 in both white and black versions for $199 with 16GB of built-in storage, and $299 for the 32GB version--both with a two-year service agreement with AT&T.
Compared to the iPhone 3GS, the device has higher screen resolution — called Retina Display — a front-facing camera, and a longer-lasting battery.
iPhone 4 also is thinner, nearly three-quarters the width of the iPhone 3GS.
It features volume and mute buttons on the side, as well as a front-facing camera and micro-SIM tray.
On the back of the iPhone 4 is a camera with LED flash. On the bottom is a microphone, 30-pin connector and speaker, while a headset and second microphone for noise cancellation sits on its top.
On the side are three slits that are part of its antenna system. The antennas built right into the phone handle Bluetooth, Wi-Fi, GPS and cellphone connections.
The phone also supports 4G data transmission, which is faster than the 3G standard, but currently not available widely.
Apple CEO Steve Jobs took the stage at the company's Worldwide Developer Conference to officially launch the iPhone 4 and other new products. Apple has often used conference to launch new products.
At the event, Jobs also announced that Netflix movies will be available on the iPhone later this year. Users will be able to resume playing a video when watching on a larger screen and then go to the iPhone.
Jobs also used his speech to tout the fact that Apple is selling about three iPads per second. The company has sold more than 2 million of the touch-screen tablets since launching the product on April 3.
Jobs also stepped to the defense of his company's app approval process, saying 95 percent get the green light within several days.