The radios and network would have to support both audio and data links. You could research if one didn't do both at the same time.
Bob
I realize that with AT&T you can talk and browse the internet at the same time but you cannot do that with the Verizon iphone 4. My question is, "Is it a software or hardware difference that makes AT&T's iphone 4 able to browse and talk at the same time but does not allow the Verizon iphone 4 to do the same?"

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