This is my first trip to France with an IPhone; in the past I used one of those cheapie Telestial phones, and as basic as it was, it worked!
I don't plan to use the iPhone much, but will have some calls to make within France while there to friends' mobile phones. When I call from here in US on my landline phone to France, I begin with 011, of course. However, French friends are giving me their mobile numbers over there that begin with 00 33, etc., instead of 011 33. Is that b/c they are mobile phones? I don't use the 011?
Thank you!

Who is your service provider and is your phone unlocked?

Grandmere,
I have an iPhone with AT&T service and an international calling plan. On that phone, the one with a US number, the AT&T rep said to make calls as if calling from the US. I had to dial 011 and the country code make any call in France from that particular phone. If you have an unlocked phone with a European phone number then the dialing convention will be different. For example, we have another iPhone which is unlocked with a UK based number and we had to dial 00 and the country code when we used that phone.

011 is the international access code to call out of the country from the US. 00 is the international access code to call out of the country from France. It is not because it is a mobile phone.

If you are using your phone with a US number to make the call, first try calling as if you were calling from the US, dialing 011 33 and then the number. From a cell phone, you can also replace the international access code by dialing a + before the country code.

That said, however, I have used my US cell phone to make calls within France by dialing the number as you would from a local French phone, without the international access code or the country code (which in France is 33).

If the French phone numbers your friends are giving you have the 00 in front of them, that is not exactly the way you would call locally. There is a 0 at the beginning of a local number that is dropped if you are calling from the US. An example:

French phone number as dialed from a US phone:

011 33 1 23 45 67 89

Same number as dialed from a French phone:

01 23 45 67 89

Tried to preview, but it posted before I could make this clarification.

If your friends are giving you numbers that begin with 00, that is the international access code. If dialing locally within France, you would not use that. Without the access code, all local calls begin with a 0, as in the example above.