Looking for a US-Based Phone Number for my Japanese iPhone

I'm looking for recommendations on getting a US phone number on
my Japanese cell phone, via VOIP. I currently have such a thing with
Skype, but their app and feature design are gratuitously stupid...
just amazingly dumb.

My needs are simple... I pay a fee to get a US-based phone number,
and when someone dials that number, it rings on an app on my iPhone. And using that same app, I can dial out. Voice messages a bonus.

I'd like to use Vonage's app (I've been a normal Vonage customer for
a decade), but it doesn't work with Japanese phones.

Recommendations?