The AT&T version of the Galaxy S5 (SM-G900A) from Samsung, is reportedly starting to receive its much-awaited Android 5.1.1 update from the carrier, as of this Friday. The phone is currently on Android 5.0 Lollipop and the current update, which comes with the baseband version G900AUCU4COI5, will bring along a number of useful feature additions, security patches and bug fixes. According to the official changelog from AT&T, the latest firmware revision will bring along a "Fix to Ultra Power Saver mode for devices using On Device Encryption", along with 'Android for Work', seeing as Samsung is one of the companies to have enrolled with Google as one of its partners in laying out the enterprise mobility management (EMM) platform.
As for the latest update being rolled out by AT&T, the file size of the download will vary between 609 to 999 MB depending on the installed build version on the phone. The OTA update will be rolled out in a phased manner throughout the country, but the availability of the update can also be manually checked by accessing Settings > Device > Software Update > Update Now. The device received its Android 5.0 Lollipop update back in April this year, and was currently on baseband version G900AUCU4BOF2 prior to this update being rolled out. AT&T has specifically mentioned on its website that the update will only be downloadable on Wi-Fi.
As a quick recap of the hardware specs of the Galaxy S5, the device was the 2014 flagship smartphone from the house of Samsung and features a 5.1-inch Super AMOLED capacitive touchscreen display, with a resolution of 1920 x 1080 pixels. The device is powered by a Qualcomm MSM8974AC Snapdragon 801 SoC, which comes with a Quad-core CPU clocked at a frequency of 2.5 GHz, along with an Adreno 330 GPU. The device came out of the box with Android 4.4.2 KitKat, but had since received the 5.0 Lollipop update, as mentioned already. The smartphone comes with 2 GB of RAM and either 16 or 32 GB of internal storage depending on the variant chosen. The Li-Ion battery that comes with the device is rated at 2,800 mAh, and imaging options include a 16-megapixel rear-facing primary camera and a 2-megapixel front-facing secondary camera.