Windows 8 key for Nokia, says Stephen Elop

Nokia has revealed its first smartphones that will run on the next version of Windows.

The Lumia 920 will come with a wireless charging pod, while the mid-range Lumia 820 has exchangeable backs.

But Nokia's chief executive Stephen Elop told the BBC's Rory Cellan-Jones that it is Windows 8 that will really make a difference in the company's bid to eat into Apple and Android's dominant share of the smartphone market.