I'll be traveling back and forth between Vietnam and the states quiet a bit. When I usually come to HCMC I just buy a local sim card to use for minutes and data but it seems like the cards expire if I'm away for more than a few months.
I do business here in Vietnam so I'm looking for a way to keep a permanent HCMC number as cheap as possible. So I'm wondering, is there a good service for a virtual phone number that I can purchase and forward the calls to any new sim cards I purchase in the future? or a do you recommend a different solution?