Technology

The new screen offers a 16:9 ratio, matching that of wide screen televisions.  But its 4in (10.2cm) size remains smaller than rival displays used by Samsung, Nokia, Motorola, LG, HTC and Sony's flagship models.

Phil Schiller - Apple's vice president of worldwide marketing, who unveiled the device - said existing apps would be shown with black borders until developers updated their products.  For Apple, the latest version of the phone which supplies the lion's share of its enormous profits was always going to be crucial to its financial future.   For the rest of the mobile phone industry, today's launch was something to worry about - how would it change this fast-shifting landscape?  With so many leaks there were few surprises about this bigger, thinner iPhone.  A better camera, more uses for the voice activation feature Siri, and its own mapping system with turn-by-turn navigation all add up to an impressive device.  But Android users, and in particular fans of Samsung's best-selling Galaxy S3 will say Apple is just playing catch-up. Features like the ability to shoot a panorama have been on their phones for years.  That won't stop the new phone being a big hit - with millions of existing users now likely to be nearing the end of their contracts.  Those who've got used to the iOS system will be keen to stay with it - while for newcomers to the smart-phone, the iPhone will be the shiny new thing.  The handset also features a new Apple-designed chip, called the A6. Mr Schiller suggested this made it twice as powerful as the earlier model.  The camera is an eight mega-pixel model - the same as in the iPhone 4S, and a lower specification than LG and Sony's most recent devices.  However, Mr Schiller said the equipment and associated software meant the iPhone would create better photographs in low light than before. The handset also uses a new, smaller, socket for its charger. This means owners will need to use an adapter to plug the device into existing speakers and other equipment.The addition of a new, and pricey, $30 adapter cable, however, has some people seeing red over all the green they're going to have to spend. One reviewer remarked, "Apple could quite happily have dropped its margins...to ensure these crummy little interconnects weren't quite so expensive."  But some economists are celebrating the prices, for the profit Apple is likely to turn could give the GDP a nice little boost. "Calculated using the so-called retail control method, sales of iPhone 5 could boost Q4 GDP by $3.2 billion, or $12.8 billion at an annual rate. This would boost annualized GDP growth in Q4 by 0.33%-point," wrote JPMorgan Chase economist Michael Feroli.