(Our happy hour fact to amaze your drinking buddies with.)

Apple has sold four million iPhones to date, averaging sales of 20,000 phones per day.

At least, that's according to what Steve Jobs told the audience at the Macworld Exposition. Apple has a 19.5 percent market share of the US smart-phone market, second only to BlackBerry maker RIM, which has a 39 percent market share.

New features available on the iPhone include a location finder, the ability to rearrange the icons and iTunes movie rentals.