Normally in United States and in many other countries iPhone is available with some carrier so to use it on any other carrier you have to unlock it.But not as Apple is selling a unlock iPhone 4 from their website which are not attached with any carrier so you can buy it for a lump sum and never worry about paying for you iPhone 4 to any carrier although you have to pay your phone bills.
The news may be not much interesting people who can buy unlock iPhone 4 from their country but this is first time in US.The news is good for those who want to pay for their iPhone 4 in one go and then use it with any carrier and can also carry it to any other country without any difficulty.
The 16GB version of iPhone is unlocked is available for $649 and 32GB version is of $749.The price is fairly less from unlock iPhone 4 available in Europe but normally most of the stuff is expensive their.Still in US you can have much fun buying unlock iPhone as you would only have the option to use AT&Ts 3G network but this offer is good for anyone who is in US for some time and then he can take unlock iPhone back to his country.
Its too hard to sell iphone used in pakistan 🙁