[gr8fl4porsche]

Partially correct about Jailbreaking.

Jailbreaking allows you to install apps that are not approved by Apple.

Unlocking allows you to use the phone on other networks.

You can Jailbreak without Unlocking.

No real warranty worries with Jailbreaking, since all you have to do before getting any warranty work done is to restore the phone with itunes.

It is simply a software modification that allows you to use another app store called Cydia.

Do a search for Purplera1n if you are interested. A quick software download, 1 click, reboot phone and you are done.