Iphone No Service After Jailbreak

Is there a way to non-download apps for the iPhone without using a program to jailbreak?

I heard that there are risks with jailbreaking an iPhone (as the service recovery if you return them a jailbroken iPhone, regardless of why you came back), but I still think that $ 5 they charge for some applications is complete garbage. Does anyone know a different way to do this?

If you jailbreak an iPhone or iPod touch you can just put it in DFU mode (Google DFU mode) and restore it. AT & T and Apple can not tell the difference (as far as ive been told).

Problem with iPhone 3g 3.1 jailbreak- No Service After Jailbreak

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