AT&T has begun rolling out the Android 4.4.4 update for their Moto X devices earlier today. This update comes with a build number 212.44.26 and has a relatively big file size, so make sure you’re connected to the WiFi before downloading the update package.
This is just a minor update which bring several bug fixes as well as optimization for the Moto X. If you’ve not received the update notification, you can manually update for device by going to Settings > About phone > System.
Source : Motorola