Originally Posted by
gfunkdave
I would just activate their carrier's international roaming feature and have them use their phone like normal. T-mobile includes free international roaming on most of its plans. Verizon and AT&T will do it for like $10/day. It's by far the easiest option.
They'll be gone for three weeks, so that would be cost-prohibitive, but I understand why you thought of it as the easiest idea.