Unlocked iPhones are an alternative for people wanting the freedom to use the cell phone service provider of their choice. In most countries, Apple has given network providers the option to officially unlock the iPhone once the customer has paid off or fulfilled the terms of his contract. Users in other locations must rely on unofficial unlocking methods to freely use their iPhones with any carrier. Installing updates differs between these two types of unlocked phones.
Officially Unlocked iPhones
In many countries around the world, including Russia, New Zealand, Italy and Thailand, iPhones can be officially unlocked. Since Apple recognizes these particular unlocked phones, you can update your phone the same way you would with a locked phone. You can do this by connecting your iPhone to your computer, opening iTunes and selecting your iPhone in the left panel. On the summary panel, click on the "Check for Update" button then download and install the update if available. You can disconnect your newly updated iPhone once you are told that it is safe to disconnect.
Unofficially Unlocked iPhones
Apple does not recognize unofficially unlocked "jailbreak" iPhones. These include phones unlocked using the popular hacks created by the "Dev Team." Past official Apple iPhone updates have included software that blocks or disables the unlocked state, and some phones have been permanently disabled, or "bricked," in attempting to update. As new updates are frequently released, you should disable automatic updates in iTunes if you are using an unofficial unlock. Check Internet forums several days after the update was released to see what effects the update has on unofficially unlocked iPhones. If the coast is clear, you may manually check for the update in iTunes then download and install it. You may also reference the source of your unlock application, since it may offer modified updates that will give you the changes to improve your iPhone's performance while avoiding ones that may not agree with the unlocked feature.