According to the vet at my practice (she graduated January 2016), some people had international plans on their phones for emergencies, but most did not find it necessary, especially with the advent of iMessage and wifi. She had a simple cheap pre-payable island phone (I think it's mostly Vodaphone there) to communicate with school & classmates, but then had her cell service turned off on her iPhone & just used it on wifi. I did a similar thing while I studied abroad in Egypt in 2010, and it was pretty manageable. She also emphasized that wifi is pretty easily accessed on campus & in lots of cafes/restaurants, but her installed wifi at home was a bit spotty, so she scheduled times to have actual Skype conversations w/ friends and family but mostly texted/e-mailed.