Be very very carefull. Because there are so many fake web sites came out recently. Do not trust names like quickpwn.com. There sites pretend to be DevTeam. Applications that those sites give you might be dangerous for your iPhone. Some sites ask for donations. Remember DevTeam don't do it.
There is only one DevTeam's site: http://blog.iphone-dev.org. When I publish news about some new version of QuickPwn, WinPwn, PwnageTool and etc, I use links from DevTeam's site. Everything else could be harmful fake.
Dev Team released QuickPwn and PwnageTool for firmware 2.1 (2g firmware, 3g firmware). It doesn't work with new iPod yet. Mac OS versions only for now.
There are so many tools, some for Mac OS, others for Windows, different versions... Complicated. So let's summerize a little bit.
If you have iPhone 3G, you'll be able to install 3-rd party non AppStore applications (through separate applications called Cydia and Installer) and run these applications. If you have old iPhone, in addition to that you'll be able to unlock the device (use with any carrier).
There are two methods: quickpwn and custom firmware method. First one is for quikly pwning and jailbreaking the device without restore. You should use it if you have unlocked device or an AT&T contract.
If you are Windows user:
Go for WinPwn. The current version is 2.5.0.2 (also called 2.5 beta-2). Download here. It supports both iPhone and iPhone 3G, firmwares 2.0, 2.0.1, 2.0.2. You can use either quickpwn or custom firmware method.
There is a separate QuickPwn tool for Windows. The current version is RC3. Download here. Do you need it? Yes, if you want to quick pwn and you do not like WinPwn (or you had problems with it).
If you're using Mac OS:
Go for PwnageTool. The current version is 2.0.3.1. Download here. Works with 2.0, 2.0.1, 2.0.2 firmwares using custom-firmware method.
There is a version of QuickPwn tool for MAC OS. The current version is 1.0.0. Download here. It works only with firmware 2.0.2. Do you need it? Yes, if you want to quick pwn.
QuickPwn is not a replacement for PwnageTool, they are different tools and provide different features, QuickPwn is for quickly pwning a device, whereas PwnageTool is designed to custom build and tailor the ipsw production process, both tools will be actively developed in the future.
QuickPwn for Windows is updated. Support for all 2.x firmwares is added. So now you can QuickPwn and jailbreak the device if it is running 2.0, 2.0.1 or 2.0.2.
DevTeam reminds that it is still beta software, so usual rules apply, no complaints if anything goes wrong and use the tool at at your own risk!
Using QuickPwn does not update the firmware itself, this tool is designed to ‘Pwn’ (the ability to install future custom non-Apple firmwares) , ‘Jailbreak’ and install Installer and/or Cydia on a given device. If your device is running 2.0.1 and you QuickPwn it, it’ll still be running 2.0.1, although it will now be Pwned and Jailbroken. It will also activate (not unlock) devices that are being used outside of their intended territories and cannot be activated using iTunes.
If you want to update to 2.0.2 then use the normal iTunes update to get to 2.0.2 and then use QuickPwn to Pwn, Jailbreak and Activate, remember that the 2.0.2 update includes a baseband update for the 3G iPhone, so depending what your long term intentions are for the phone, update wisely, of course in the upcoming PwnageTool application you’ll be able to create a custom ipsw without the baseband update enabled.
It is available for download here, but beware this is still beta software. It is fairly self explanatory and easy to use. You’ll still see a command-line window popping up when the actual QuickPwn process takes place, but the device and ipsw selection is handled by the GUI.
DevTeam created a quick solution for jailbreaking an iPhone. It is called QuickPwn. It is in beta, so be careful. It will allow you to pwn (jailbreak) your device very quickly without restoring!
Who should use this tool? This is for those that are not planning to restore. It’s not clear what the activation state is after the process therefore, I only recommend this for those that have a contract carrier or an unlocked phone already.
If you are on a stock device and using AT&T or a contract carrier, this is the perfect jailbreak for you. You will not lose your contacts or have to do any backups. Finally, if you are going to restore anyway, especially if you need to unlock a 2g, you may as well use winpwn or such.
Currently QuickPwn requires your device to be running version 2.0.1 of the iPhone/iPod firmware. And it runs only on Windows. This requirement will change in a subsequent release.