What are the advantages of having a jail broken iPhone 4?

I'm considering jail breaking my iPhone but I want to know what I would get for it. What are the advantages and disadvantages of jail breaking it? Is it worth it?

Jenn's right

IOS Jailbreaking is a process that allows devices running Apple's iOS operating system (such as the iPad, iPhone, iPod Touch, and recently Apple TV) to gain full access (root access) to all features of the said operating system, thereby removing limitations imposed by Apple.

But you should note that iPhone jailbreak is an adventurous operation. You should be careful not to lose data during the process. So backup your data before iPhone jailbreak.

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