Hello I'm about a month my mother will be traveling to Israel and I was wondering if there was a way to se up an obihai with Google Voice so that she would be able to make calls from over there to the US for free? And if so how would I be able to set that up for her? Thanks in advanced!
That kind of seems like overkill unless she doesn't have a smartphone. If she has a smartphone just install hangouts and get a google voice number and be done with it. She will be able to call out on wifi or data.
If you are dead set on using an obi though, Just configure one at home and make sure you can call from it. She should be able to take it and plug it in to a router there and it will work. A couple of years back I set one up from the states that was taken to Isreal and that is what I did.
Misha11 is correct, do the setup in the USA and make sure the OBi is set for DHCP not a static IP. It should work without any additional settings. I have multiple OBi's I have setup for family and friends in South America and Italy and had no problems.
You might consider having her use WhatsApp, that works like a charm all over the world.