I think a tmobile USA prepaid
sim is her best option. It's 10 cents and
25 cents per SMS and MMS respectively to any where in the world. And
it's free to receive both (Unlike over there, free incoming SMS and MMS
is rare here). Also, they are the easiest to get. She can an already
activated and loaded with about 150 minutes minutes on ebay for about
$10 and have it shipped to her. Shipping within US would be free. If
she adds $100 topup she will automatically get 1 year expiration and
become a "gold rewards" user . Buying on ebay will also let her know
the number and give it out before leaving. She can change the area code
if she wants, but there is no need, because long distance within the 48
states is already included. It also includes free (limited) tzones.
Please visit tmobile USA's website for more details.
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mrcamp