iPhone 2G and iPod touch 1G do not officially support iOS 4. However there is a project called WhiteD00r that aims to bring iOS 4 functionality to iPhone 2G users with a custom firmware bundle.

This bundle is created by Matteo Morando and is based on firmware 3.1.3. It is built with PwnageTool. It incorporates several utilities to adds iOS 4 features such as multitasking, wallpaper, tethering, sms count, and more.

There are 3 different versions -- Lite and Full for iPhone 2G and one for iPod touch 1G. Here is the complete feature list:

Take a look at video demo:

You can download custom bundle on the official whited00r project site here.

DevTeam released update to their PwnageTool jailbreak utility. New version 4.01 supports iOS 4 jailbreak for iPhone 3GS (old bootrom), iPhone 3G and iPod Touch 2G (non-MC).

You can download the latest version here.

We recommend to read DevTeam instructions here before you start.

Hacker msftguy created unofficial PwnageTool which allows to upgrade to the pre-release of iOS 4.0 GM while keeping your jailbreak and old baseband.

This is not an official release by Devteam, so we recommend to wait for the final versions of both iOS 4.0 and PwnageTool.

For the advanced users who want to experiment here is a link.

Msftguy also provided a video:

If you want to install Android on your iPhone 2G/3G it is now very easy. Site FunkySpaceMonkey shows us how to do it.

You will need:

• Jailbroken iPhone 2G or iPhone 3G running firmware 3.1.2 (NOT 3.1.3).
• The device should be jailbroken with PwnageTool, RedSn0w or Blackra1n. Won’t work with Spirit.
• OpenSSH installed with default password (alpine)
• Macfuse installed on your Mac
• iPhodroid

How to:

• Download iPhodroid and extract
• Install Macfuse
• Run iPhodroid and hit run – the process should take around 5 minutes

The BlackSn0w Unlock utility by Geohot has been updated by MSFTGuy and PushFix to work with the latest firmware 3.1.3. However it works only with baseband 05.11.07 (!!!).

This modified version of BlackSn0w works for iPhones upgraded with PwnageTool or Sn0wbreeze, preserving the baseband version 05.11.07. Users who have updated to OS 3.1.3 by any other method have the 05.12.01 baseband so BlackSn0w and UltraSn0w will not work.

This new version of BlackSn0w will be very useful for iPhone 3GS OS 3.1.3 / Baseband 05.11.07 users who can’t downgrade to earlier versions but still need unlock.

According to iHackintosh, this new version also fixes a small bug making WiFi much more stable.

Blacksn0w RC2 will be available on ModMyi repo soon. If you don’t want to wait just add the source http://cydia.pushfix.info/ to Cydia and install it now.

Important: Blacksn0w for 3.1.3 is still in RC stage and there may be some issues or bugs. This is not an official update performed by Geohot, who has clearly indicated that he will not be updating any tools for the 3.1.3 firmware.