Apple boss Steve Jobs has revealed that the company has sold its 4 millionth iPhone.

Speaking at the Macworld keynote in San Francisco, Jobs said the company has been selling 20,000 iPhones per day on average, since it went on sale in the US last June. Today is the 200th day since it shipped.

The Apple founder also revealed where the iPhone stands in the US smartphone market. RIM remains the market leader with 39 percent, according to the stats revealed by Jobs, but the iPhone is gaining ground with 19.5 percent of the market. Palm (9.8 percent), Motorola (7.4 percent) and Nokia (1.3 percent) make up the rest of the top five.

As well as revealing impressive sales of the iPhone, Jobs has announced new features for the handset. He said iPhone users will soon be able to make clips of their favourite sites and put them on home screen. A new "plus" button has been added to the iPhone's bottom toolbar, allowing iPhone owners to "Add to Home Screen" along with an icon. The icon then appears on the home screen, just like an application.

Apple has also simplified the Maps interface with Search and Directions buttons at the bottom. The view button on the bottom right 'peels up' the map and gives you the option with the Map, Satellite, Hybrid, and List views. Pressing the button in the bottom left locates you.

In the demonstration on stage, Jobs typed in 'Apple' for the End direction, and the iPhone shows the route back to Apple - a mere 47 miles. Plus, you can edit the directions - Jobs showed the directions to the Apple Store. You can also drop a pin anywhere you want and move it around. You can add it to your bookmarks, move the pin, etc.

Plus, iPhone users can look forward to multiple SMS text messaging via an update Apple will release shortly.

More details to follow...

Further announcements surrounding the MacBook and other Apple products, possibly including the iPhone, are due to be announced within minutes. Check the PC Advisor home page frequently to get the latest news as it happens.