From what I have gathered on this forum as well as the other resources, it appears that the best and most cost-effective option for cell phone use in Paris would be to unlock my current iPhone and have a French/International SIM inserted during my time abroad.
I will be studying abroad for 3 months in Paris and plan to do some traveling within the EU on weekends. I plan to mainly utilize WiFi to my fullest advantage when communicating with friends and family in the US through FaceTime, WhatsApp, Skype, iMessage, etc, but I also hope to be able to communicate at least sparingly with classmates and friends who are also in Europe. I plan to minimize my usage to solely several calls and texts a day when WiFi is inaccessible. If anyone could provide any insight or advice based on experience, I would greatly appreciate it! Also, if you have any suggestions of French/European carriers, that would be extremely helpful.