iPhone 3G

[madeleina]

How to turn off 3g on the iphone? I'm planning to buy and iPhone 3G from ebay, but i don't plan to have a data plan for a few months. Now what I'm scared of is that I'll accidently browse the internet on the 3G signal instead of WiFi, causing receive a huge bill for it from AT&T. Is there a way to turn of 3G data, yet keep the calling and wifi features on at the same time via setting or something?
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