Alzinho is so right, Kirst. They are all very expensive and credit tends to last no time at all, especially if you call rather than text. Choosing between the different companies is almost impossible as there is not a clear market leader. My advice would be to buy a really cheap phone: the most basic Nokia you can find, so that its loss is not a matter of consequence and when you return you simply get it out, put in a new card and go. And as Alzinho says, get a card for the company that gives you access to the majority of your friends. And then use text wherever possible as it is so much cheaper than calling. Do bear in mind that your card will be discontinued by the company if it is not charged with credit after two months.