If you're an iPhone user with an AT&T contract waiting to make the leap to another carrier, your jail breaking days are over.
The wireless service provider announced that on Sunday, April 8 AT&T customers with expired contracts will be able to unlock their phones and use any other service they like — except Verizon.
Seeing that AT&T and T-Mobile operate on GSM networks while Verizon and Sprint operate on CDMA networks, iPhones sold through AT&T have different hardware than those sold through Verizon or Sprint, making it impossible to switch GSM-enabled phones to Verizon.
What's more, there are a few caveats before you liberate yourself. According to a statement from AT&T, "… a customer's account must be in good standing, their device cannot be associated with a current and active term commitment on an AT&T customer account, and they need to have fulfilled their contract term, upgraded under one of our upgrade policies or paid an early termination fee."
So in plain English, your account needs to be all paid up, with no long-term contracts, and no outstanding balances.
If you qualify, call AT&T on April 8 for an unlock code. Once you receive the code you'll have the freedom to use a SIM or micro-SIM from another carrier.
From VentureBeat, Engadget