Wi-Fi calling comes to the AT&T Samsung Galaxy S7 and Galaxy S7 edge
AT&T's Wi-Fi calling is a great feature to have in areas where the carrier's signal is not very strong. If you can't get a call out on AT&T's network, look for a viable Wi-Fi signal in the area. Once you connect to that signal, you can use Wi-Fi calling to make that call, send a text, or listen to visual voicemail messages. Today, an update sent out by AT&T to subscribers with the Samsung Galaxy S7 and Samsung Galaxy S7 edge adds Wi-Fi calling to those phones. The new software version is MMB29M and the file is roughly 600MB.
If you can't wait for the notification to appear on your phone telling you that the OTA update has arrived, you can check it out manually. Go to System > About device > Software update > Check for updates. So let's say that the update has arrived. Before you start the process of downloading and installing it, make sure that you are connected to a Wi-Fi network. And you should also make sure that your battery is fully charged before going ahead with the update.
source: AndroidCentral
Besides adding Wi-Fi calling to the handsets, the update comes with the July security update, changes to Setup and Transfer, and the inclusion of AT&T's advanced messaging system (IPME).
source: AndroidCentral
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