fwiw...i had go around with several att'ers and did get provisioned correctly so my side-loaded vvm.apk from the op was working on my $30 lte data unlimited w/visual voicemail. no transcription of the voice to text though. when they moved me to $30 lte data unlimited and added the feature for voice to text for $3.99 the vvm.apk transcribed text.
click image to enlarge: Attachment 1014520
i'm using messages since it transcribes for free and hopefully the messages tablet app gets updated soon to work even better that it currently does so texts and vmails are read, replied to, and managed from tablet just as easy the phone.
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