1st problem is Verizon phones are CDMA and AT&T phone towers are GSM, so if where you are does not have a CMDA tower that partners with Verizon, you will not be able to send/receive SMS or get voice calls.
Data still works providing there is an LTE band signal available to you.
I read about chatsim.com/en just now, and did not know anything about it, having zero need for it myself.
What I don't see mentioned is, will it work with skype to allow you to access a Real World telephone number? messaging services, like what ChatSim just mentioned will not provide you with voice calls unless that is handled somehow....
as I said, I know zero about that service.
I have direct experience with if where you are does not have a CMDA tower that partners with Verizon, you will not be able to send/receive SMS or get voice calls.
There is a town called Winston, MO, USA and AT&T is the only game in town. it is a barren desert for Verizon for some reason. I was there for 24 hours to attend a funeral, and never once was I able to make a phone call or send out a SMS message... I had to use WiFi to access the internet and from there, I accessed Verizon's Texting service to send out a message to all that I cannot make/take phone calls or messages until I leave that town.
