Nexus 5 and Gvoice

[eco7]

Hi @all,

I have my GN5 with a T-mobile sim card and I just order a Google voice number. My question is, what do I need or what others Apps to activate my Google number to work overseas and as my second number. I will be traveling to Germany for 1 year and I would like my family to be able to call me on a local number in order to save some money and not on long distance calls.

Thanks