Data may be blocked if you are trying to use an iPhone on ATT's prepaid or post-paid service. Other services are probably going to be easier in this regard.
There are some workarounds I saw mentioned @ howardforums & one of the major apple/iphone forums, but I probably shouldn't post anything as such- to be respectful of the rules here.
Trying to go the cheapest route, a buddy told me I can buy a used iphone that has been unlocked/jailbroke, and activate cell service through Wal-Mart for $30 month unlimited talk & text. I will use wi/fi at home and work, but can also buy a pre-paid data card from Wal-Mart.
Has anyone gone this route? The pros would be saving money, I am looking for cons, like getting ripped off buying a used phone.

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