The iPhone was first announced on January 29, 2007, with a release date of June 29, 2007.
Apple's first smartphone, and all subsequent models, utilized the iOS operating system. Originally released on the Cingular Wireless network -- later to become a part of AT&T -- the iPhone did not appear on another network for four years as the result of an exclusivilty deal. The iPhone is now available on AT&T, Verizon, and Sprint.
Since the original iPhone, Apple has introduced a single new generation of the device each year. The family of Apple's smartphone line includes the iPhone, iPhone 3G, iPhone 3GS, iPhone 4 and the iPhone 4S, in order of release.
Adding to iOS, Apple launched the App Store on July 11, 2008.
While the first three iPhones can be considered iterative of each other, aside from the inclusion of 3G online connectivity starting with the iPhone 3G, the first major change came with the iPhone 4.
The new design, front facing camera, and Apple's Retina Display, has since carried over to Apple's fifth phone, the iPhone 4S.
