During his keynote speech at the Moscone Centre in San Francisco for the opening of Macworld2008, Steve Jobs revealed that four million iPhones have been sold to date.

This figure is particularly significant as the date of Steve Jobs' speech - the 15th January - is the 200th day since the iPhone has been on sale, meaning that 20,000 iPhones have been sold each day the device has been on sale.

Jobs revealed that in the first quarter of the iPhone being on sale, it achieved a market share of 19.5%, putting it in second place.

On the subject of the iPhone, Jobs moved on to talk about the new features that the latest iPhone update will bring.

The new functionality that firmware update 1.1.3 will offer iPhone owners will include improved mapping that can find a user's location, customisable homescreens and the ability to SMS multiple people at once.

Other improvements include more language support in video, lyrics support in audio and webclips.

The improvements to mapping come in via cellphone signal triangulating, as the iPhone obviously does not contain a GPS chip.

Jobs rounded up the iPhone section of his speech with the statement that this update is "available today as a free software update for every iPhone".