Is an iPhone price war about to break out in the UK? After Vodafone and Orange bagged the iPhone - when O2's two year monopoly expired in September - we learn today that Tesco, the UK supermarket leviathan, is to sell the iPhone on Tesco Mobile, its MVNO joint venture partnership with O2. This news just sent the iPhone directly into the mainstream. UK iPhone app developers are looking at an even bigger gold rush than before. Both iPhone 3G and iPhone 3GS handsets will be sold in Tesco Phone Shops and online through Tesco Direct in the UK, possibly before the Christmas holidays. Tesco Mobile normally focuses on the low end of the market with voice and text, and we're told the prices will be "competitive". As an MVNO, Tesco has a fairly free hand regarding the the markets it goes after. O2 says it has sold over one million iPhones since September 2007, clearly to early adopters.