Why and How I Jailbroke my iPhone
Posted by onlydarksets on October 6, 2008
Or, “How I Got My iPhone to Do This”:
I finally broke down and jailbroke my iPhone. My motivation was that June Fabrics developed PdaNet for the iPhone, but it was rejected by the App Store, so they released it on Cydia. However, once I jailbroke, I found a wealth of apps out there that fill in most of the missing pieces.
Keep reading for the full details.
What is “jailbreaking”?
Jailbreaking is a type of PWNing an iPhone that lets you install applications on it other than those in Apple’s official App Store. “PWN” more generally refers to any iPhone hack that allows you to do things with your phone that Apple didn’t intend (keep it clean – you know what I meant). PWNing includes unlocking (i.e., using on different carriers), modifying the baseband, and changing the IMEI number.
Once you jailbreak, there are two apps that are installed that function similarly to the App Store – Cydia and Installer. Cydia and Installer are essentially catalogs of applications that can be installed on a JB’d iPhone. They can co-exist with no adverse effects. Installer came out first, then it seemed Cydia had the lead for a while, but now both seem to be actively developed and have current repositories. I mostly use Cydia, so here is a walk-through of how Cydia works. For most people, that is all you need to know.
What’s the risk?
The downside is that JB apps have full access to everything. The Apple SDK sandboxes each app – each app only has access to read and write to its own folder, and apps aren’t allowed to access many core system functions or run in the background.
JB apps aren’t bound by these limitations, so they can read/write anywhere, access any system functions, and run in the background. So, while an App Store app can only destroy itself, a JB app can destroy itself and the OS.
That said, I don’t think the concern is something malicious, because everything is distributed through the repositories. If you use a trusted repository, you shouldn’t be exposed to anything dangerous (but, of course, there are no guarantees). However, the consequence of working outside the SDK is that sloppy code can have more of an impact with JB apps than App Store apps.
So, that’s pretty much the “why” of it.
How do you do it?
There are a number of apps that will let you do various types of PWNing. If all you want to do is to jailbreak (again, installing custom applications), there is a ridiculously easy way to do it, thanks to a tool called QuickPWN. That’s all I wanted to do, so that’s what this post focuses on. You could also use tools such as ZiPhone and WinPWN, which will jailbreak, in addition to custom firmwares.
No, really, how?
You can find step-by-step instructions via Google, but here’s an example. Note the following:
- Make sure you select the option to install Cydia during the jailbreak process. I also selected “Installer” – they can run together with no known issues.
- As of October 4, 2008, you cannot unlock a 3G iPhone. Accordingly, you can skip the steps (and downloads) for bootloaders.
- If you have already upgraded to the latest firmware, you don’t need to download the firmware – QuickPWN will find the firmware already downloaded on your PC.
OK, now what?
Start installing apps! Find the Cydia icon and run it – it will download the latest list of applications. I suggest starting with the “Featured Packages” link on the main page of Cydia. You can also install programs by using the Search button on the bottom.
Here’s what I installed to get the screencap above:
- Five Icon Dock – Adds 5th app to the dock
- AT&T Carrier Logo – replaces the AT&T logo with the globe and “at&t”
- StatusNotifer – show email/call notification icons in the tray bar
- Winterboard – install custom icons, wallpapers, etc.
- OpenSSH – full access to the file system via a SSH or SFTP client
- MobileTerminal – full access to the file system from the iPhone
And, of course, there is an almost limitless number of other things you can do:
- Run any application in the background (Backgrounder)
- Tether to a laptop (PDANet)
- Use an application launcher (QuickGold)
- Display calendar/email/etc. data on the lock screen (IntelliScreen)
- Download and save locally files via Safari
- Use the built-in camera for video recording (Cycorder)
- One-stop preference setting (BossPrefs)
- Video game system emulator (NES)
- Offline Google Reader (GRIS)
- Download files directly to folders via MobileTerminal (curl or wget)
Where did you get the app icons?
Theming is a whole separate post, and there are plenty of guides out there already. However, I culled my icons from these two sources:
- http://www.spaziocellulare.com/ispazio/themes/theme_categories2.php (registration required)