03-14-2011, 09:36 PM
Dunno about data, but for voice any unlocked GSM phone will be fine. Jailbreaking has to happen first, then unlocking is one of many things you can do to the iphone after JBing. Buy a sim card locally on the street, load it up with however many $ you want. Takes 10 min. South America is a big place and the best providers will vary.