Apple's iPhone 5 goes on sale Friday, starts at $199

Apple Inc will begin taking orders for the iPhone 5 on Friday, costing $199 for the cheapest 16 gigabyte version to $399 at the top end.

Shipments begin on Sept 21, and the smartphone will be sold in 100 countries by the end of the year.

The latest iPhone comes as Apple tries to fend off competition that has reached fever-pitch. Google Inc's Android has become the most-used mobile operating system in the world, while key supplier and rival Samsung Electronics <005930.KS> has taken the lead in smartphone sales.