The iPhone Dev Team has released a Windows version Redsn0w for iOS 4 (0.9.5 BETA). At this point, iOS 4 is still only available for developers, but the GM release has been widely leaked all over the internet. iOS 4 GM does not require iPhone Dev account to install, so a lot of folks have updated early. Although you can jailbreak iOS 4, there is still not a lot in Cydia that are compatible with iOS 4.

The redsn0w beta has been updated for 4.0GM on iPhone 3G and iPod touch 2G (non-MC version). Multitasking and homescreen wallpaper are turned on by default (Apple doesn’t normally allow this on these 2 devices). You can deselect these features if you choose.

A version for Windows is now provided.

Just like our other betas, this one intentionally doesn’t “hactivate” the iPhone. Please wait for Apple’s public release of 4.0 for that part of it.

YOU SHOULD STAY CLEAR OF THIS BETA SOFTWARE IF YOU RELY ON A CARRIER UNLOCK. That’s because the beta redsn0w works only if your device has already been upgraded to the stock 4.0beta1/beta4/GM IPSW from Apple, which contains a baseband update. If you installed that IPSW, you’ve already lost the carrier unlock until the next planned release of ultrasn0w and blacksn0w.

This is a beta release of redsn0w targeted at developers of jailbroken apps. It uses the same pwnage2 DFU-mode exploit that we’ve been using since the 2.x days. Nothing new is revealed to Apple, and it’s not applicable to the iPad. Don’t go near it if you use yellowsn0w, ultrasn0w, or blacksn0w.

Please note that this beta is not meant for the average end-user. There are many things “broken” with jailbroken apps in the 4.0 environment right now (that’s the real reason we showed “Veency” in the 4.0 jailbreak demo video back on April 9, instead of say MobileTerminal.app, which is broken!). This beta redsn0w allows the developers behind those jailbroken apps (like MobileTerminal.app!) to fix their software before the general public gets iOS 4.0.

Because it’s meant for JB app developers, this beta redsn0w does not perform hactivation. You’ll need a properly-registered developer UDID with Apple to get past the activation screen. For similar reasons, there is no Windows version of this beta redsn0w (since apps are developed on MacOSX). Please don’t pirate Apple software.

Anyone other than developers of jailbroken apps porting their software to 4.0 should still be using our previously-released redsn0ws for 3.0 through 3.1.3

If you want to use Redsn0w to jailbreak you can download it here.