To jailbreak your iPhone or iPod touch, all you need to do is download PwnageTool, launch it and follow its directions. Using its "Simple mode," the utility walks you through the needed steps. The only misstep, when I tried it with my iPod touch, is that the utility did not alert me to Option-click the Restore button in iTunes, instead of just plain clicking Restore. The Option option is needed so you can select the special custom Restore.ipsw file that PwnageTool creates. As the last step of the jailbreak, your device restarts and displays a pineapple icon, instead of the familiar Apple icon. Cute.
When done, you have a functioning jailbroken iPhone. It all worked without a hitch when I gave it a whirl. I can now add jailbreak software alongside programs downloaded from the App Store. All is well -- except for one thing: There isn't much jailbreak software to install. Virtually all of the jailbreak software that you could run on a pre-2.0 iPhone is not available for 2.0 devices.
Previously, I had jailbroken my iPhone (running 1.1.4) using ZiPhone, which apparently will not be updated to work with 2.0 software. This (and a few other similarly functioning utilities) jailbreak the iPhone using a different technique than PwnageTool. From a practical standpoint (and ignoring some internal political debates between developers in this area), one big difference between ZiPhone and Pwnage is that ZiPhone puts Installer on your iPhone (a utility that I have covered in detail in a previous column) while Pwnage uses Cydia.
Both Installer and Cydia function in a similar way to allow you to install additional programs on your iPhone or iPod touch. However, after completing my 2.0 jailbreak and launching Cydia, I was disappointed to find that almost all of the programs I had installed via Installer on my 1.1.4 iPhone were not listed. At first, I thought that this might be some Installer vs. Cydia difference (with Cydia on the losing end). However, according to the FAQ that accompanies Cydia, the real problem is that almost all pre-2.0 jailbreak programs are currently incompatible with iPhone 2.0 software -- and so are not listed in Cydia. The older software should eventually be updated and "ported" to Cydia but, for now, "you will have to be patient." Bummer!
If you do decide to jailbreak your iPhone, I strongly recommend you read the entire Cydia FAQ before you start complaining about its limitations. The FAQ provides a good summary of the current state of affairs.
I did have one glitch with all of this. After selecting to update or install software from Cydia, the installation appeared to hang (the sundial "cursor" kept spinning and never went away). Eventually, I gave up and did a force quit of Cydia (by holding down the iPhone's Home button). I have already had to do this twice. All was well after relaunching Cydia, including finding that the software had successfully installed. Still, this has made me a bit nervous about Cydia's reliability.
Because of such concerns, I don't yet intend to extend my jailbreaking from my iPod touch to my iPhone. Before I mess with my phone, I want to be absolutely convinced that there are no negative side effects lurking in the shadows -- and that there is enough software available to make the jailbreak worthwhile. If and when that day arrives, I'll jailbreak my iPhone and (of course) I'll let you know how it goes.