T-Mobile recently announced their new early upgrade plan for smartphones, and now AT&T has followed suit with the AT&T early upgrade plan which is called AT&T Next.
AT&T Next will let you upgrade your smartphone once every 12 months, and there is no down payment, no activation fee, no upgrade fee and no financing fee.
The customer can trade in the device after 12 months, or they can keep using their device and have no more installment payments after 20 months. Beyond the monthly device installment, there’s no additional monthly fee required to participate in AT&T Next.
So basically in order to upgrade you will need to trade in your old smartphone, you can find out more details about the plan over at AT&T.
Source Phandroid