Unlocked means that you are not “locked” to a single carrier, so yeah you can use other countries SIMs.


I can share my experience from a recent trip to Germany. While there I bought a pay-as-you-go Constar SIM with 15 Euros on it, for 9 Euros. (It generally came with 10 Euros on it but it was some sort of Christmas special.) That allowed me to call or text any German number for 9 cents (per minute or text). Calling other countries from Germany had different rates. I cannot remember the exact rates but it was something like 1.25 Euros for a US cell line and .70 euro for a US land line. Data was H most of the time and coming from Virgin Mobile US’s crappy speeds, it seemed really fast to me. Data costs were brutal, so I generally had data turned off and used Wi-Fi when I could.


On a side note if you have a Google Voice number and supporting app like GrooveIP you can text and make called for free back to the US using your Google number. Well free as long as you are on Wi-Fi. Hope that helps.

 

I know nothing about the Moto G, but any unlocked GSM phone should be the same.

 

It will come down to which frequencies are supported if the device is unlocked. Most come with the standard 850/900/1800/1900 for GPRS & EDGE, but HSPA frequencies will vary from device to device.

 

You mentioned you are on TMo. I don't know which plan you are suing but you may not need to purchase a SIM when you are traveling internationally. TMo has a very competitive international roam plan. No roaming fees, free text and data. High speed data is capped but you won't get whacked with a huge surprise data charge.

You have to make sure it is a country that is included in TMo's plan. You can get the details here: International Service

FYI, I spend about 30% of my time in Europe and this is one of the reasons I'm switching to TMo. As a matter of fact I'm in Zurich right now.

 

My GSM Nexus 5 works ideally world wide. Bought it from Google play, installed my T-Mobile sim and all is good to go.

 

I did take a look at T-Mobile's Simple Choice Plan. It is too expensive for my limited use. But I can see how it would work for someone who spends a lot of time overseas.