We are taking our first trip to Mexico (Puerto Vallarta) later this month and we are bringing along our iPhones. I've never taken the iPhone out of the country, and am seeing all kinds of horror stories about charges, roaming, etc. The resort we are going to does have WiFi and a cool app - Connectivity App - that looks like it will be really helpful. Can anyone point me at some tips or provide some here, if you have any experience? Like I said, I am only there for 4 days. Should I get a different plan via AT&T (my carrier) for the trip? I have unlimited data and messaging (grandfathered in). Thanks for any help!