So i recently got into the jailbreaking "business", and it took a lot of time to learn it all. But first, for the ones who dont know, Jail breaking is when you connect your Ipod, iphone, or any apple device to your computer, and run a Program to it that Cracks the devices Code, and allows you to run any code on your device.
The whole point of jailbreaking is to get a program called "Cydia" on your ipod or iphone. This Cydia Program, or "App" lets you change your themes, colors, designs, download 3rd party apps, and customize it to how ever you like. Even change the Boot image from the white apple, to any image you want. Some people also may do it for their iphone so they can use the iphone on other networks Besides ATT. So people can use it in countries that it is not allowed if they want.
This is from Wiki: "Once jailbroken, iPhone or ipod users are able to download many applications
previously unavailable through the App Store via unofficial installers
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