San Jose (California)
I will be traveling for 2 weeks through Italy, Paris, and London. I am going to bring my iPhone 5 which is unlocked and allows me to put on a cell phone sim from an overseas carrier. Does anyone recommend a particular wireless carrier for that coverage? I am looking for little to no phone calls and mostly data coverage to retrieve emails and upload pictures and videos.
I was in Italy for a month last year and I purchased a prepaid sim from TIM that included calling and data for my unlocked Verizon iPhone 5. It worked like a charm and was really cheap. You have to bring your passport in, so don't forget it. Make sure to test out the SIM while you are there, before you pay. My friend had an AT&T phone, but it might not have been unlocked because the SIM didn't work and they were nice and didn't make him pay for it even though they already activated it.
My experience in France was with Orange. They are everywhere in the country (boutique style stores) and it´s the best price found. Other friends have tried it and had the same comments.
Jenifer is right: TIM is the best carrier. You find stores easily and the employees are friendly and know how to deal with tourists and their needs. Also, TIM offers good Internet plans and you'll just deactivate your SIM before leaving.
Enjoy my country! :)
Vodaphone or O2
When I was in London, UK I purchased a prepaid card from Three http://three.com/
Since I mostly use data I selected unlimited data (All you can eat) and 200 minutes of calls.
That was 15 GBP only.
The data speed was real good and a lot lot lot faster than you can ever have in the US.