Here you have it, the pro and con:
So what's the benefit of jailbreaking your Apple product anyway? Unauthorized applications – specifically, you can now fire up third-party app libraries like Cydia to install apps you wouldn't otherwise be able to find on the official Apple Store. And these, in turn, can help you customize your device beyond what Apple itself would ever allow you to do, which includes turning your device into a Wi-Fi hotspot (and angering your wireless carrier in the process).
The downside to jailbreaking? You void your Apple warranty and could waste precious hours begging Apple Genius Bar employees to make your iPhone 4S or iPad 2 better should some part of the device's software or hardware go buggy. You're also likely going to be stuck waiting when future iOS updates are released, as you won't want to install Apple's update without first verifying that your jailbreak will still be able to function.
