I have a iPhone which was purchased in United states. It was used there for sometime too. When it came here my friend helped me unlocking and jailbreaking it. It was succesful and is working fine now. I was thinking of doing an system upgrade on that phone. Someone told me that if I do it just like that it might mess up the phone. There should be some way to upgrade an unlocked iphone 4. Please share on thoughts on same.
