San Francisco - Apple CEO Steve Jobs introduced the second generation of the iPhone, called iPhone 3G, during his keynote presentation at the World Wide Developer Conference on Monday. The new iPhone sports 3G wireless data networking and a built-in GPS, and a substantially lower price tag.

iPhone 3G will support both 3G (quad-band GSM and tri-band HSDPA) for voice and data along with the EDGE standard found on the original model. It will also include Wi-Fi support for wireless network access.

iPhone 3G

The built-in GPS will support real-time location tracking and mapping, and will offer improved accuracy over the Wi-Fi and cell tower-based locator that the first generation iPhone offers.

The new model is thinner than the original iPhone, includes the same display found in the first model, and a black plastic back. It also sports better battery life with five hours of 3G talk time, ten hours of 2G talk time, 300 hours in stand-by mode, up to six hours of Web browsing, seven hours of video playback, and 24 hours of audio playback.

iPhone 3G owners will also be able to use their third-party earbuds and headphones without special adapters since the new model includes a flush-mount headphone jack instead of the recessed version found on the original model.

The new iPhone will ship with iPhone Software 2.0 with support for Apple's App Store so users can download and install third-party applications.

The iPhone 3G will be available with 8GB of storage for US$199 and 16GB of storage for $299. It will be available on July 11 in 22 countries, and will roll out in over 70 markets over the next few months.

[This article has been updated with additional information about iPhone 3G.]