How to multitask on iPhone iOS 4

We have spent a chunk of today eagerly playing with our iPhone’s new operating system, iOS 4.

There has been plenty of discussion about iPhone multitasking on Twitter, so I thought I’d post a quick summary.

Gizmodo explains it well:

Double-clicking the home button will open a tray showing all running applications. Switching to another running app is as simple as clicking on it. It works like the task switch bar in Windows or Mac OS X.

This should work on iPhone 3GS and 3rd generation iPod touch. Engadget writes:

The iPhone 3G and below won’t — Steve says the hardware doesn’t support it. Sad face.

As the Apple site says:

Now you can run your favorite third-party apps — and switch between them instantly — without slowing down the performance of the foreground app or draining the battery unnecessarily.

Are you excited? What’s your favorite new feature in iOS 4?