I think this question was addressed in an answer to an earlier post. Did I read correctly that when you buy a SIM card in Europe for an unlocked iPhone 5, the phone number changes? This would work very well. I have no experience with replacing SIM cards or buying international phones so am absolutely clueless.
Every SIM card has own unique number. Again, my admonition --- nano SIM cards are not easy to find.
If you want a US phone number (assuming your live in the US?) while in Europe, get a free Google Voice phone number, then install Google Voice and Google Hangouts on your iPhone. Then you can make/receive calls on this US phone number via Google Hangouts using WiFi or data on a new SIM card. That phone number would NOT change with a different SIM (which would give you a separate phone number local to that SIM's country), so you could test this out before going to Europe.
You could even forward calls from your regular cell phone to your Google Voice number, so you can still receive calls/voicemail while in Europe.
I wish I could use Google Voice, but the phone I have is one my son gave me, and I am waiting for my Verizon contract to expire before actually using it. Consequently, that's why I was hoping that a European SIM card would provide it's own phone number. Of course, I could be blathering nonsense.
i'm not sure you understand what Google Voice is. It doesn't replace your existing phone service. You can use it right now on a Verizon phone, without changing or canceling a contract, oron any phone that is on WiFI or has some data connection. You can even use it on a desktop computer. It's kind of like Skype, but it also works with regular phones not just computer to computer.
Google Voice requires an existing phone service just to sign up - you have to provide them with a phone number (even a landline number), then they give you another phone number.. If you have a US Verizon phone number now, you can use that. Calls people make to your Google Voice number would then forward to that phone number - but you can also receive them without any phone service, using the Google Hangouts app (which, again, is something like Skype).
The original point of Google Voice was to give you one portable phone number for various phone services: if you had a landline years ago and a cell phone, you could attach them both to Google Voice, and someone could call your Google Voice number and it would ring both your landline and your cell - and could answer whichever is most convenient. The person calling you doesn't have to know which phone they are calling - doesn't matter. Of course, many have dumped their landlines nowadays so that doesn't make as much sense anymore - but you can still kind of use it that way if you have multiple ways to receive a phone call: maybe your Verizon phone is one, maybe Google Hangouts on a smartphone is another...
Yes, a European SIM will provide its own (European) phone number. If you don't need to have a US phone number or aren't worried about the cost of calling back to the US with your European SIM account, you don't need to bother with Google Voice. But I've been using Google Voice for years (even before I had a smart phone) and like the fact that I can use it for free in Europe to make/receive calls home to the US, with the same phone number I normally use at home.
Yes, the number does change with each SIM card, as does the account details and network. For example, if you buy a SIM card from O2 Telefonica in the U.K., your number will be a U.K. number and your account details will be determined in accordance with the plan you choose at the time of purchase.
For changing the SIM card, you may find THIS VIDEO helpful.
I doubt that you'll have much trouble finding a Nano SIM card, since Europeans also use the iPhone 5 and above.
Thank you both for taking the time to answer my question. So much to learn! My ipad has a phone number attached to it. Does that mean I could use Google Voice with that?
Yes, you can use Google Voice on your iPad, with the Google Hangouts app. Or on the iPhone at the same time. You still need to go to Google Voice and sign up and get a phone number first, before you can receive any calls. I think you can make calls OUT with Google Hangouts without having a Google Voice phone number.
Thanks again for you time. This is very helpful.
Yes, you get a new phone number assigned to your phone. The only hick-up is dialing back to the U.S., you may need to change the contacts in your contacts list to dial "+1."
While in London, it took me 5 minutes and 20 pounds to have a SIM with 2.5GB of data and 300 minutes of voice ($0.05 to U.S.) installed at an O2 store. Best thing I've EVER done while traveling overseas!
Be sure to take a SIM extractor tool or a paperclip with you so you can remove the SIM upon return. If your phone is on a GSM network at home, you need to take something to keep the original SIM in until you return. A plastic SD memory card case works well... The process for removing/inserting SIM cards is pretty straight forward. (Even I mastered it in no time.)
BTW: Due to the popularity of the iPhone 5 and iPhone 6, I have never had a problem finding nano SIMs in Europe.