This post is part of a 4 part series that overviews jailbreaking, addresses common misconceptions about the process, discusses its pros and cons, and describes how perform a jailbreak on iOS 6 on your iPhone, iPad (Mini), or iPod Touch.

If you’ve been around the world of iOS devices for any length for time, chances are you’ve heard someone mention jailbreaking. There are many benefits to jailbreaking an iOS device, and also many misconceptions that go along with the process. In this post, part 1 of a 4 part series on jailbreaking, I will provide an overview of jailbreaking and outline some of the major features that become available once a device is jailbroken.

What is jailbreaking?

Jailbreaking, in short, is a process that exploits an iOS device’s software or hardware, removing limitations and allowing the user to install apps, modifications, and themes that are not available on Apple’s App Store.

Apple has included a number of safeguards in iOS preventing users from running software that has not passed its strict App Store approval process. Additionally, Apple has prevented users from installing any modifications to iOS’ stock user interface. The reason Apple has done this is to protect users from nasty things like viruses and also to ensure a seamless and bug free user experience. For most users of iOS, this approach is very beneficial and makes iOS an extremely easy to use and stable operating system. However, circumventing Apple’s safeguards by jailbreaking can be a great option for power users, those looking to extend the functionality of their iOS device, or people who want their iOS device to stand out in a crowd.

How does jailbreaking work?

Jailbreaking provides a user with root access to iOS, allowing non-Apple-approved software to be installed. This is accomplished by exploiting an iOS device’s hardware or software. Most often, a software program on a Mac or PC is used to perform a jailbreak.

There are two types or levels of jailbreaks: tethered and untethered. A tethered jailbreak requires an iOS device to be connected to a computer and exploited with jailbreak software each time it’s booted up in order to hold its jailbroken state. With an untethered jailbreak, which is much more useful and difficult to develop, a user can reboot their device without being connected to a computer while retaining their jailbreak.

The actual method of jailbreaking an iOS device can vary greatly depending on the version of iOS being run and the tool being used. Depending on the methods used to jailbreak a device, the software solution may create and install a custom modified IPSW, or Apple Software Update File, which includes the jailbreak. The user must then use iTunes to install the custom IPSW. Other software solutions offer a one-click solution for jailbreaking a device. One of the most important things to understand about jailbreaking is that a jailbreak solution does not exist for every iOS device or every version of the iOS operating system. Usually, one major, untethered jailbreak solution will be released for most devices per yearly update of iOS. Often, Apple will then patch the exploits used to perform the jailbreak with the next minor update to iOS, rendering the jailbreak ineffective on systems updated past that point.

Who develops jailbreaks?

One of the exciting things about jailbreaking is that jailbreak developers often work on exploits independently or in small teams and in their spare time. It’s amazing to see the final jailbreak tools that these devs come up with. Developing a jailbreak tool for a new version of iOS is much like a fencing match, with developers looking for weaknesses in iOS’ defenses. The process of finding enough exploits to release a jailbreak tool to the public often takes months from the time Apple releases a new major version of iOS.

Cydia

In addition to jailbreaking iOS devices, every major jailbreak tool installs an app store: Cydia. Cydia has been around since the early days of jailbreaking and, much like the App Store that comes bundled with iOS, allows users to search for and install software. However, the primary differences between Cydia and the App Store are that Cydia only runs on jailbroken devices and that it downloads and installs apps, modifications, and themes that have not been approved by Apple. Cydia uses what are called repositories, or “repos” for short, that act much like channels from which different software packages can be downloaded. Just like Apple’s App Store, some of the packages on Cydia are available for free and some cost money.

Benefits of Jailbreaking

Aside from simply being able to download apps that haven’t been approved by Apple, there are number of things that a jailbroken device can do that a stock one cannot. For the purposes of this article, I will organize the types of packages available on Cydia into three categories: apps, modifications, and themes, and provide a few examples in each category.

Apps – Many apps on Cydia are inventive in their approach and function. And since they don’t have to conform to Apple’s restrictions their function can be much broader than apps on the App Store.

One example of such an app is f.lux. This free app, also available for Mac and Windows, gradually warms the color of the device’s screen after sunset to help promote healthy sleep patterns. There is a lot of research that suggests that looking at the blue light that normally comes from a computer or smartphone screen at night can cause problems with humans’ sleep cycles. The warmer toned screen f.lux provides is definitely much less painful to look at in the dark.

Another free app that extends the functionality of iOS is Airfloat. This app turns an iOS device into an Airplay receiver, allowing a user to stream music to their device over a wireless network from another iOS device, Apple TV, Mac, or (with some work) PC.

Modifications – One of the biggest benefits to jailbreaking an iOS device is that many packages on Cydia allow users to modify the way they interact with their device. For example, take two stalwarts of the Cydia Store: Activator and Zephyr.

Activator, a free tweak, allows the user to assign system functions to a variety of gestures. For example, the user might create an action that locks their device when they swipe from right to left across the status bar. Or a user might tell Activator to open the Settings app when they tap the screen with four fingers.

Zephyr is a tweak that allows the user to employ fluid swipe gestures to control their device rather than relying on its physical buttons. With Zephyr installed, users can swipe up from the bottom of the screen to access the multitasking tray rather than double-tapping the home button. Swiping onto the screen from the right or left allows users to switch between running apps without even invoking the switcher. When in a running app, swiping up from the bottom of the screen sweeps the app out of the way and returns the user to their home screen. Zephyr’s swipe gestures feel very natural and much less abrasive then using an iOS device’s physical buttons to navigate.

A third package available for free on Cydia that increases a device’s ease of use is NCSettings. This package places a row of toggles in iOS’ Notification Center, so that the user can easily switch on and off Wi-Fi, Bluetooth, Cellular Data, enable or disable Airplane Mode, change volume or screen brightness, and much more. This saves the user from having to access settings through iOS’ Settings app each time they need to turn something on or off.

Themes – Another benefit to jailbreaking a device is the installation of themes, packages that change the very look and feel of the operating system. Most themes are applied using a free app called Winterboard, which is available on Cydia. Themes often redesign everything from app icons to menus to buttons to lock screens. Themes are abundant on Cydia, and many of them are terribly designed. However, there are a few that stand out from the crowd and, according to your tastes, may actually improve the look and feel of iOS.

Two of my favorite themes that are brilliantly designed are Ayecon and Aplo.

Ayecon, an incredibly detailed theme called developed by a designer who calls himself Surenix, uses every pixel on a device with a Retina Display to its fullest.

Aplo is a theme with an eye toward simplicity and richness and was created by a designer named Sentry.

Installing a theme on an iOS device can really set it apart and make it unique.

Jailbreaking an iOS device provides the user a level of customizability that is not available on a stock device. If this article has been your first exposure to jailbreaking, you are likely interested but have some questions or reservations about its legality, safety, and the potential for the process to permanently harm your device. In Lesson 2 in this series, we will dive into some common misconceptions about jailbreaking. Also, check out Lesson 3: Pros and Cons of Jailbreaking and Lesson 4: How to Perform a Jailbreak.