AT&T updates Samsung Galaxy S4 to Android 5.0.116
The update adds the new Material Design UI, battery features including longer battery life and "time left to recharge" data, and the ability to access the Quick Settings menu with a two-fingered swipe down from the top of the screen. Priority mode allows only certain kinds of notifications to be read, and the Smart Lock lets you pair your phone or tablet with a secure device like a car or a wearable.
Since the update is rather large, AT&T is demanding that you are connected to a Wi-Fi pipeline when downloading and installing it. And when it comes to your battery, you should make sure that your cell is at least 50% charged up before beginning the updating process. Because the update goes out in waves, it might not reach your phone for a few days. So if you look for Android 5.0.1 on your AT&T branded Samsung Galaxy S4 and it's not there, there is no need to panic. The update will eventually hit your phone.