How to perform a iphone 4 update?

iPhone 4 is the latest available version of iPhone from Apple. As you may know, iPhone runs on a operating system called iOS and it can be updated through iTunes, another software from Apple. To update your iTunes to the latest iOS, at first you need to download iTunes first from Apple's website. iTunes is available in both Windows and Mac OS X flavours. Depending on your operating system you are using on your PC, choose the appropriate version of iTunes and install it on your PC. If you're using a Mac, a version of iTunes is already installed on your computer, use 'Software Update' to update it to its latest version before proceeding to update iOS.

When iTunes is installed or updated to latest version, use the following steps to update iOS on your iPhone 4.

1. Connect your iPhone 4 to your computer. You'll find an accompanying USB cable in your phone's box that will let you connect the phone to your computer.

2. Select your iPhone when it appears in iTunes under Devices.

3. A new window with a number of tabs will open. Select the Summary tab.

4. Click on Check for Update in this tab. iTunes will start looking for available updates for your device. Upon finding a applicable update, it'll download and install the update on your iPhone. Do not unplug your phone before the update finishes. That could lead to complete unresponsiveness of the device.