original Apple iPhone smartphone. iPhone 3G comes with iPhone OS version 2.0 which features various new features and improvements over its predecessor, most notably the App Store.
New features also included are Apple's MobileMe service, Microsoft Exchange ActiveSync support, and push email support. Apple iPhone 3G supports GSM, EDGE, HSDPA, WiFi, Bluetooth, and GPS. Aside from the new 3G radios and frequencies additions, iPhone 3G has essentially identical hardware specs to the original iPhone e.g. the display is still the same 3.5-inch capacitive touchscreen with 320 x 480 pixels and the similar 2 megapixel camera. However it has plastic back instead of an aluminium one on the original iPhone.
Apple iPhone 3G also intros MobileMe service that is able to push email, contacts, and calendars from an online "cloud" to native applications on Apple devices. If you have more than one Mac, you can use MobileMe to keep your email, contacts, calendars, and bookmarks in sync across all your Mac computers and even a PC. For more specific info about Apple iPhone 3G, there is a table of specification with more detailed information on the Apple iPhone 3G Specs.