What is ESN and why do i need it?

So i have an iphone 5 and i want to buy an iphone 4 or 4s to customize it and jailbreak it. I don't need an apple warranty on it and i was looking online on ebay for one but most say bad ESN. I don't think this would matter because i'm planning on unlocking it and using Straighttalk or nothing at all for calling/messaging, since i already have a phone. It is basically a supped up IPOD i want to use it for. So does a bad ESN even matter for what i want to use it for?

Added (1). Thanks!

The ESN is the phones serial number. As long as you never want to activate the phone ever, a phone with a bad ESN can be used as an Ipod.

Straight Talk will not activate a phone with a bad ESN.

Its stolen

  • What is ESN stand for and what does it mean? I'm trying to sell a iphone so i was trying to average out the price.people state bad ESN and stuff like that. So i need to know what it is. And when you answer don't say anything that involves CDMA ensles you identify what that is too.
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