iPhone 4s canadaian

I'm not really familiar with the MagicJack app, but it looks like it makes use of a data connection. So, if correct, if you only connect your iPhone over a free wifi connection, then, yes, I think you can probably use it. In that sense, it would work like Skype does over a wifi connection. For Skype, once you're on the Internet, it will treat your calls to a U.S. or Canadian number as if you were calling from home. A call to a local (that is, foreign) number will incur whatever MagicJack charges for the same call if you made it while in Montreal. If you try to connect over the phone network, however, and you are using you home phone network connection, you will be hit with a massive bill for roaming data usage.

Maurice, I don't have a definitive answer for you, however a few thoughts..... You should be able to use your MagicJack App in Europe, however as Paul mentioned if you access the data network via 3G there could be HUGE BILLS. That would restrict you to making or receiving calls only where Wi-Fi is available. When travelling with a Smartphone, it's VERY important to switch off data roaming unless you're using a travel plan or travel SIM. Which cell network are you with? On the topic of making calls, I suspect you would be able to make calls to Canada, since you'd be accessing the public telephone network via the MagicJack Servers and the call would be routed as if you were at home. However, I don't believe you would be able to make calls locally in Europe. Your call would again be routed from the MagicJack Servers, which would then have to access any one of a number of Public Switched Telephone Networks in Europe. The MagicJack website states "when you travel outside of the country you will have free calls back to the U.S. and Canada", but it does NOT mention anything about making local calls to Europe (at least that I could see). I'd suggest you contact MagicJack for a definite answer to this question. IMHO, it seems like a rather "awkward" system to travel with. Happy travels!