Alright folks. I’m going to try and break it down simply as I possibly can - and I’m not sure if even that’s good enough. For starters, I’m going to split each section by phone. You should probably read about your phone if you want to jailbreak and unlock it.

First, here are some terms.  After reviewing these, skip down to your phone to find out more information and firmware links.

PwnageTool

A Mac tool to jailbreak iPhone 2G, iPhone 3G, and iPod Touch 1G.  This will also unlock iPhone 2G.  This tool will create custom IPSW to flash your device with.  To use it, you must download the firmware to be able to modify it.  This post has all of the latest firmware links in their respective sections.

download mac (sha1 2e19d39398233f88ae0782fd82462a9223791f7f)

redsn0w

A Mac and PC tool enabling you to jailbreak iPhone 2G, iPhone 3G, iPod Touch 1G, and iPod Touch 2G.  This also unlocks the iPhone 2G.  You can use this after an official update or restore (through iTunes), which means not using a custom built firmware.  This is the quickest method of jailbreaking your device - previously known as QuickPwn.

Update:  redsn0w is was just updated to 0.7.2.  Fixed are for PPC and Icy.  New links are posted below along with new sha1 sums

download mac (sha1 0d58ff133461f3487a80200fe924741dd393b724)

download pc (sha1 444a3120b6bfd98838df74d598d3799cf656dfff)

Just a note for Windows users - if you’re having a problem extracting the files on Vista or Windows 7, I would suggest using a third party archive tool such as 7zip.

ultrasn0w

The latest development from the iphone-dev team.  This is the soft unlock for 3.0 (baseband 04.26.08).  This is not released as of this posting.  It will be available (as far as I know) via Cydia, just like yellowsn0w)

iPhone 2G

Current jailbreakable & unlockable firmware:  3.0 (iPhone1,1_3.0_7A341_Restore.ipsw)

The iPhone 2G remains unlocked.  It will always remain unlocked.  Pretty self explanatory.  You can update at any time and jailbreak - your phone will remain unlocked.

iPhone 3G

If you rely on yellowsn0w for cellular service, DO NOT UPGRADE TO 3.0!  You must be patient.  ultrasn0w is coming and once it’s out, you’ll be able to upgrade and have an unlocked 3.0 iPhone 3G.  And yes, this will work for ALL iPhone 3G!

Current jailbreakable firmware:  3.0 (Phone1,2_3.0_7A341_Restore.ipsw)

As for providing the links, these are for reference.  You are going to need the firmware file in an accessible place if you plan to use the dev-team tools, as all of them require you to select the firmware.  Again, iPhone 3G is 3.0 jailbroken, but NOT unlocked!

iPhone 3GS

Current firmware: 3.0 (iPhone 2,1_3.0_7A341_Restore.ipsw)

Easy:  not jailbroken, not unlocked.  However, the iPhone 3GS has the same baseband (04.26.08) as the iPhone 3G 3.0 firmware.  I believe if and when the iphone-dev team jailbrake the 3GS, it wll be an instant unlock because the exploit is already found.  Well done, Apple - and thanks @Oranav!

Good news folks.  pH, BigBoss, and EvilPenguin have created a tool to downgrade your baseband from 02.30.03 to 02.28.00.  What does this mean for you?  Well, if you upgraded (on purpose or accidentally) to 2.2.1 - then you have 2.30.03, which is not supported by yellowsn0w.

The only downside to this:  the iPhone 3G has two bootloaders:  5.8 and 5.9.  According to http://thebigboss.org, “if your iPhone was manufactured before September (2008), you are 5.8. Otherwise, you are 5.9 (that can’t be downgraded)”.

A quick and easy way to tell when your phone was manufactured is by looking at the 11 digit serial number located on the lower back of the phone.  The first two digits are the factory ID (where it came from), and the next three are date information.  The rest of the numbers are irrelevant for our purposes of downgrading

It’s digits 3-4-5 of your 11-digit serial number. The first two are the factory ID of which it was made in, and the next three are date info. I don’t know what the rest of the numbers are for.

Example:  xx832xxxxxx.  The 8 represents the year 2008.  This is the first good sign for your iPhone 3G.  The next two numbers is the week it was created.

From what I’ve come up with - if you have lower than week 36, you should be okay.  Week 36 is the end of September.  Can we get some comments to confirm this?

So to install this beautiful piece of work, you can find it on TheBigBoss repository on Cydia.  It’s called “3GBBD” (3G Baseband Downgrader).  Just download and click go - and you should be on your way!

These notes are DIRECTLY from the http://thebigboss.org post:

WARNING: This tool is NOT a toy. Just use it if you can’t use Yellowsn0w on your 2.2.1 iPhone 3G. Otherwise, DO NOT INSTALL IT JUST TO TEST! YOU HAVE BEEN WARNED!

Edit: if you have bootloader 5.9, this should not cause any harm. It should simply fail. You will then have to reboot your iPhone and should be back up to where you were before running the tool.

Big thanks to pH, EvilPenguin, and BigBoss http://thebigboss.org for this wonderful tool!