I am going on a quick 3 day cruise to Mexico in a few days. I don't intend to use my phone very much except to take a few pics (I like the geotagging feature when it uploads to iPhoto). I may want to check my email occasionally. If I enable Airport mode I'm not able to make or receive calls, right? Does that turn off all data options? If I don't enable Airport and my push email still comes through, will I be paying roaming charges for that?