AT&T's Samsung Galaxy S4 Active receives update to improve connectivity
This year, the regular Samsung Galaxy S5 features IP67 certification, and the Samsung Galaxy S5 Sport (an AT&T exclusive in the U.S.) comes with rubber bumpers and some protection from drops. Meanwhile, on Thursday, the Samsung Galaxy S4 Active received an update from AT&T. The update improves connectivity on the device, allowing for improved reception of calls and texts. The update is coming OTA and AT&T is demanding that you use a Wi-Fi connection while downloading and installing it.
Before you proceed with the update, AT&T recommends that you backup your media files to a microSD card. You can also backup your content using Samsung Kies. While the update started rolling out on Thursday, don't panic if it doesn't come to your phone immediately. Updates like this one are sent out on a staggered basis, so if it doesn't come today or tomorrow, you will get it shortly.
source: AT&T via AndroidCentral