Jailbreaking your iPhone or iPad is a risky process that we can't unreservedly recommend, but it remains popular among those who wish to install unofficial apps (such as those on the Cydia marketplace) on their smartphone or tablet. Here's how to jailbreak your iPhone or iPad in iOS 7 - and iOS 6 and earlier. Updated 17 January 2014, to add the new iOS 7 jailbreak tool, and then again on 23 January to add news on the iOS 7.1 jailbreak block.

UPDATE: After the recent release of a jailbreak tool for iOS 7 (detailed below), it's been reported that the next version of iOS, iOS 7.1, patches the loophole that made that possible - although this version remains in beta. A member of the Evasi0n team that produced the jailbreak tool has spoken about the relevant patch on Twitter, and it seems likely that a new jailbreak tool will have to be created in response to iOS 7.1. Check out the deails in our iOS 7.1 features and updates roundup.

(What is jailbreaking? In essence it means bypassing the locks put in place by Apple on its iPhones and iPads, and thus gaining access to a large number of apps that Apple hasn't authorised. For explanations of more Apple-related terms, see our Apple jargon-buster encyclopedia.)

How to jailbreak an iPhone: A warning

But first... Some of the unofficial apps that you'll get access to after jailbreaking are pretty tempting, and may offer features you'd never otherwise be able to access; blocking a phone number on an iPhone, for instance, wasn't possible officially until iOS 7 launched, but an app on Cydia (where you can download apps for jailbroken iPhones and iPads) let you do it easily. Read: Pros and Cons of jailbreaking an iPhone.

Cydia on iPhone

How to jailbreak an iPhone: Cydia is the app that lets you browse and download further unofficial apps

So why doesn't everyone jailbreak? Well, for one thing it's by no means straightforward, as we'll see shortly. Jailbreaking is also legally ambiguous, risky, and prone to void any warranties you have with Apple. We advise you to think long and hard before going ahead with the jailbreaking process.

Apple itself offers advice on the subject of jailbreaking (although you may feel that the company is biased in this respect, since it wants to continue getting its cut of the revenue from official app sales). In this tech note Apple suggests that jailbreaking your iOS device may lead to security vulnerabilities, instability, shortened battery life, unreliability, disruption of services and inability to apply future software updates. It may result in Apple denying service for your device.

Nonetheless, many Apple fans have been jailbreaking iOS devices for years without encountering these issues. But once they've jailbroken such a device, they understand that they should expect no help from Apple if it causes them trouble in the future. With choice comes responsibility.

How to jailbreak iOS 7 (and iOS 6 and earlier)

We had to wait for a bit, but the jailbreak tool for iOS 7 has been launched by the Evasi0n team. (The Evasio0n team offer one word of warning, however: "Over The Air updates of iOS 7 are known to create an issue and make the jailbreak fail. Some devices are then stuck on the Apple Boot Logo. Until we fix that, please restore your device to 7.0.4. with iTunes first.")

UPDATE: iOS 7.1, which is still in beta, is set to close the loophole that allows Evasi0n's iOS 7 jailbreak tool to work. Bear this in mind when considering whether to update your operating system to iOS 7.1 when the full version comes out.

Before you start, back up your iPhone or iPad, and switch off the passcode (at least for the duration of the jailbreak process).

Before jailbreaking, be sure to back up your data

You’ll need to download the Evasi0n7 tool, which is available for Mac OS X and Windows, and is compatible, the makers claim, with all models of iPhone and iPad running iOS 7.0 to iOS 7.0.4. The tool is available from mirrors on evasi0n.comDouble-click the .dmg file to decompress it and an evasi0n window will appear on your desktop. Drag the evasi0n application out of the window to the desktop and launch it.

Connect your iOS device and click the Jailbreak button. evasi0n will retrieve some information from your device. The device will then reboot and prepare itself for the jailbreak. Don't do anything with your device during this stage.

evasi0n begins its work

evasi0n will now install Cydia - the application that provides access to third-party apps - on your device. When instructed to by evasi0n, unlock your device by pressing the Home button and swiping the Slide to Unlock switch to the right. You should see a new Jailbreak icon on your Home screen. Tap it and evasi0n will carry on with the final stage of the jailbreak. You can now quit evasi0n by clicking the Exit button.

Don't touch your device until evasi0n tells you to

Your device will reboot, briefly display the evasi0n screen, show the Apple logo, and then show the evasi0n screen again, which details the progress of the jailbreak installation. Finally, your device is ready for you to use in the normal way.

The one difference you'll see is a Cydia icon on the home screen. Tap it and Cydia launches, prepares its file system, and then quits. To then use Cydia as intended, tap its icon once again, choose your user type (User, Hacker, or Developer), tap Done, and the Cydia interface loads.

The version of Cydia you're using may need updating; older versions of Cydia may not support Cydia's newer third-party apps. To do that, tap the Changes icon at the bottom of the screen and then tap Refresh in the top left corner. If any updates are available (as evidenced by green check marks) tap the Update button in the top-right corner of the display. Cydia will download the latest updates and reboot the device.

What you choose to install is entirely up to you. Some people choose to install OpenSSH so that they can remotely access the device's file system via a standard FTP client. However, if you enable this feature, be sure to change your device's root password from the default "alpine," which is used by all iOS devices. Fail to do so and others around you could hack into your device. To learn how to change the password, tap the Root Password How-To link on Cydia's About screen.

Cydia is now in the house

How to jailbreak an iPhone: Future updates of jailbreaking tools

There was a decent wait between Apple releasing iOS 7 and a jailbreaking tool being released for the system - most likely because iOS 7 represented a more substantial update than most new versions iOS. As Apple releases minor and major updates to iOS, new jailbreaking tools (and updates to tools) will be released too, but there may again be a wait.

If you want to keep track of when jailbreak tools are launched in the future, two useful options are following @evad3rs on Twitter (that's the account used by evasi0n), and checking out the jailbreaking section on Reddit.

In the mean time, look out for scammers. Lots of unscrupulous companies and individuals claimed to have cracked iOS 7 before a reliable tool was released by the Evasi0n team, and offered to give you the jailbreak for a sum of money - often $50.

How to jailbreak an iPhone: tethered and untethered jailbreaking

Finally, some words on jailbreaking terminology.

Jailbreaking has been in a largely dormant state since the release of iOS 6. In that version of the mobile operating system, Apple closed many of the avenues that had once been used to crack iOS open.

Tethered jailbreaks require you to attach your iOS device to your computer and run an application to jailbreak it. If you later power off the device and then restart it, the jailbreak is wiped out, and you have to repeat the entire process.

These kinds of jailbreak were the first to be developed. But what prospective jailbreakers wanted was an untethered method, where the hack would remain in effect even after the device was switched off and on again.

That untethered jailbreak arrived in the form of evasi0n. Like jailbreaks before it, evasi0n doesn't unlock an iPhone (which would allow you to use the device with multiple carriers). Rather, it simply allows you to install third-party apps not approved by Apple via the Cydia store we mentioned earlier.

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See also:

Opinion: Why I continue to jailbreak

Should you risk jailbreaking your iPhone?

iOS 6 untethered jailbreak released, Cydia app store flooded

How to update your iPhone or iPad to Apple iOS 7

How to stop iPhone neck and iPad shoulder

How to fix a water-damaged Apple iPhone

How to protect your iPhone from thieves