[blageo23]

Alright I'm a but if a tard when it comes to this.
Let's say I got an iPhone 4 used on AT&T. When the new 4s comes out I upgrade to it. That means the iPhone 4 is uncontracted correct? Now does that mean its unlocked? If not how would I unlock the 4 to use with a different carrier?
I'm trying to sell my 4 and it seems the unlocked ones go for quite a bit more money.
Sorry for being a noob