The seven tentpoles: iPhone OS 4.0's new bank of features

At Apple's press conference in San Francisco today, Steve Jobs and the Apple team showed off the latest iPhone operating system, and the plethora of features that are packed in the new download.

The keynote showed off seven major tentpole features for the smartphone's next firmware, which are as follows:

iPhone users will now be able to run multiple apps concurrently and switch between them. Tapping the home button twice shows a nifty pop-up dock, with the icons of currently running apps.

The apps aren't actually running in the background though. They're frozen in a save state and will be restored when you're next using them, to save on memory and battery.

Or, developers can use one of a bunch of multitasking APIs to keep certain functions of their apps going once the program is switched. Pandora can keep playing music, Skype can keep calls going and Tom Tom can keep giving directions.

You will be able to throw your apps into folders simply by tap-and-holding an icon and dragging one on top of the other.

The iPhone will give you a neat pop up drawer full of apps, and even try and give it an intuitive name based on the genre of apps in that folder.

This extends your home screen from about 180 apps to well over 2,000.

Prettify your iPhone with new backdrops, just like the new iPad. You'll be able to choose from changing your lock screen or home screen wallpaper when you choose that option in your photo library.

Unified inbox

Instead of swapping between inboxes all the time, iPhone users can have all their emails collected in one unified inbox. You'll also have access to multiple Exhange accounts, threaded messages and, if you don't want to use the unified inbox, switch between inboxes much faster.

Exactly like the iPad's virtual bookshelf, but now you can take your purchases with you on any device you want.

A centralised gaming service like Xbox Live, Game Center helps gamers connect to each other. You'll aso get a single user log-in, unified achievements, leaderboards and a friends list. What this means for services like OpenFeint and Plus+ is anyone's guess right now.

Apple's own advertising platform keeps you in the ad instead of kicking you out to Safari or the App Store. You can watch videos, play games, read text, and even buy apps from within an application.

Another iPad carry over - wireless keyboards for typing on the go.

Faster focus times and further zoom for iPhone directors and photographers.