Determine your current device software version and check for updates.
INSTRUCTIONS & INFO
VIEW DEVICE SOFTWARE VERSION: Press the Rotating Side button from the clock-screen. Note: The images and steps in this tutorial reflect the latest software version (Android 7.1.1). For more information on the latest update available for your device, check att.com/softwareupdates.
Here you can view the software version.
UPDATE DEVICE SOFTWARE: from the About screen select System Updates. Follow the on-screen prompts to update your device.