Apple says pre-orders of its iPhone 5 topped two million in just 24 hours, more than double the previous record of one million held by iPhone 4S.

Demand for iPhone 5 exceeds the initial supply and while the majority of pre-orders will be delivered to customers on Sept. 21, many are scheduled to be delivered in October, according to Phi Schiller, Apple’s senior vice president of Worldwide Marketing. “

The iPhone 5 will be available at 356 Apple retail stores in the US beginning at 8 a.m. local time on Friday, Sept. 21. Every customer who buys an iPhone 5 at an Apple retail store will be offered free Personal Setup service, helping them customize their iPhone 5 by setting up email, showing them new apps from the App Store and more.

The iPhone 5 comes in either white & silver or black & slate, and will be available in the US for a suggested retail price of US$199 for the 16GB model and $299 for the 32GB model and $399for the 64GB model. It will be available from the Apple Online Store (www.apple.com), Apple’s retail stores, and through AT&T, Sprint, Verizon Wireless, select Best Buy, RadioShack, Target and Walmart stores and select Apple Authorized Resellers. The iPhone 4S will also be available for $99, and the iPhone 4 will be available for free with a two-year contract.

The iPhone 5 will roll out worldwide to 22 more countries on September 28, including Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, Hungary, Ireland, Italy, Liechtenstein, Lithuania, Luxembourg, Netherlands, New Zealand, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden and Switzerland.