I am going to cancel my phone plan in U.S as it's astronomically expensive when we use our data and make calls abroad. I'm moving to Europe and will be in Prague for my 1st month. Can anyone help me with some advice on how best to use an iphone that I already have, to set up with temporary service in Czech republic? I can't sign up for a year contract. Just want a phone that can make phone calls when necessary and that I can use even when there's no wifi. For safety and directions reasons.