I was also wondering this before and have done some research on it. I believe the visual voicemail app is for the people who pay the separate fee att charges for the visual voicemail feature. But, we can get free visual voicemail through the att messages app. I just turned off text message notifications in the settings. I tried to find a way to make the voicemail tab the default view when I open the app but haven't found a way. So I just live with it and press over to the voicemail tab. Hope this helps some.
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