A free app for Android, by Free Mobile Unlocking.

This app is a handy tool for unlocking the Sony mobile phone on the AT&T network, even for the latest models. This tool can be used on all Sony devices, including the Sony Z, ZR, W, W205, and other phone models. It is very easy to use, and it provides a lot of options for you to choose from.

The first thing you need to do is download the app and register for an account. You will receive a code via in-app notification, and you will need to enter it in the app. The code will unlock your device for a very low price.