Find out how you could update the iPhone, iPad and iPod Software to the latest version of iOS.
Keeping the software on your device up to date is critical as the new version can fixes many bugs and problem that you may already have. At the time of this article the latest version iOS is 4.3.2.
Here's how to update your device.
1. Plug your device into the computer using the provide USB cable.
2. Start iTunes 10.2.1.
3. A message automatically pops up offering you to Download and Update (Windows) or Download and Install (Mac OS X). Click on the download and update button to proceed.
If you want to download the IPSW file directly then you can use the below links.