The Reason for Jailbreaking the iPhone

The reason for jailbreaking your iPhone is pure and simple – to have the ability to install 3rd party apps not sold in the App Store. I know there are thousands of apps available in the app store, but apple has been very restrictive with their rules regarding which apps can be made available to users. A few of the functions that jailbreaking can supply include, video recording, tethering, multi-format video playback, copy/paste, turn by turn talking GPS navigation, Bluetooth file transfers, power management, MMS, Voip over 3G, instant messenger in the background, brighter flashlight, customized menus, and stolen phone recovery.

If jailbreaking is so great, why doesn’t everyone do it? Well, in a world of OS X and Windows, we are used to using non-customizable and unstable computer environments. Given these issues with computers, we all fear our devices crashing, so we try never to fiddle with it too much. But instead of just telling you that the iPhone is different, why don’t we go over the most common reasons I hear on why people do not jailbreak their iPhone.

 

1. I don’t like to break the warranty.

While jailbreaking your iPhone does break the software licensing agreement, it does not break the warranty of the phone. And technically once it is restored back to it’s standard configuration (unjailbreaking), you are no longer invalidating any agreements. If you ever have any hardware issues, just unjailbreak your phone and send it in. As of yet, jailbreaking your phone is not illegal.

2. I’m afraid it will kill my phone and lose all of my information

As for jailbreaking being the cause of a bricked phone, I have found less than a dozen instances of people having unrecoverable issues and they happened with older jailbreaking methods. From the research I have done, even the worst jailbreak failures can be easily fixed by putting the phone in recovery mode and recovering with iTunes. Then you just re-jailbreak. Regarding information loss, you should always backup your contacts through iTunes or through Gmail.

3. It is only for people who want to be different

Jailbreaking is not only for people that want to be different and personalize their phone. While it offers many options to customize your menu and tailor it to your personality, there are many apps that offer basic functionalities. I do not think that being able to record video, copy/paste, or talking turn by turn navigation is a matter of trying to be different.

Tethered Jailbreak

Tethered means being basically "attached" to your computer in a way; you must boot your device by running code on it (via the dock connector) to make use of an exploit.


Description

Devices are tethered because there is one or more area where the device fails one or more signature check along the way due to the jailbreak. The device is able to boot up because there is a way to execute code via USB that allows you to bootstrap to a pwned (no signature check) iBSS, iBEC, or iBoot to finish the boot process.

What is Untethered Jailbreak

An untethered jailbreak is a type of jailbreak where your device does not require you to reboot with a connection to an external device capable of executing commands on the device.

iOS Support
Many device/firmware combinations can use an untethered jailbreak. The most current version of iOS (4.2.1), as well as the iPod touch 4G, can be untethered jailbroken already.
Devices as new as the Apple TV 2G have known bootrom exploits. However, the iPhone 3GS old bootrom and older have bootrom exploits that allow for an untethered jailbreak. Newer devices as old as the iPhone 3GS new bootrom, iPod touch 2G new bootrom, and iPod touch 3G have bootrom exploits that are limited to a tethered jailbreak (without the assistance of a firmware-based exploit).