Mostly anything that is in the advanced calling menu.
On the unlocked phone you will only have the option to activate Volte. Any other HD Voice functions will not be available on the unlocked version without some hacking.
Verizon in a petty nickel and diming anti consumer corp. that will swindle or coerce you into spending more for less service and punish you for daring to try to save a buck by buying an unlocked device without all their storage consuming bloatware that they configure in such a fashion that you can't remove it from the very phone that you paid for.
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