The iPhone 5 will support 21Mbps HSPA+ data networks, China Unicom vice president Huan Wenliang said during the Macworld Asia 2011 conference. T-Mobile and AT&T both offer 21Mbps HSPA+ connectivity in the United States and market the networks as “4G,” although a recent letter from T-Mobile’s chief marketing officer suggests T-Mobile USA will not carry the device. The image above shows Apple’s progression from EDGE on the original iPhone to 3G support on the iPhone 3G, 3GS and iPhone 4 and, finally, to “4G” support in the iPhone 5. We reported exclusively in August that Apple is currently in a carrier testing stage with a 4G LTE-capable iPhone, too. Apple is set to unveil its latest iPhone on October 4th and current reports suggest the Cupertino-based company will reveal the iPhone 5 as well as a watered-down iPhone 4S device. Rumors suggest the iPhone 5 will offer an 8-megapixel camera, a thinner and lighter aluminum unibody design and a larger display.