A scant 17 days after Apple released the iOS 4.0.1 update, a Web-based jailbreak is available for the iPhone 4. The problem is that the server -- at JailbreakMe.com is slammed as of this writing and it's difficult to get through.
It works like this, just navigate to JailbreakMe.com from Safari on your iOS device and touch the graphic at the bottom to "slide to jailbreak." (I know, tricky huh?)
It currently runs on:
iPhone 4 on iOS 4.0.1
iPhone 3G on iOS 4 and 4.0.1
iPod touch on iOS 4
It fails on the iPad running 3.2.1
Some report losing MMS
JailbreakMe didn't initially work on my iPhone 4 running 4.0.1 (Safari hung on the purple background screen), but I rebooted my phone and repeated the process again and it worked.
Here's the best way to get Cydia installed on the iPhone 4:
Once completed, you should have the Cydia app on your desktop, although it may take a reboot to make it show up.
If Safari hangs, trying rebooting the iPhone and look for Cydia on the desktop. If it isn't there, try repeating the steps above again.
After it didn't work the first time on my iPhone 4, I got this error message the second time that I went to JailbreakMe.com:
On my second attempt, the package successfully downloaded (it took about five minutes):
Once the process is complete, you'll see a message like this:
Now it's off to install some apps!
Update: As reported earlier JailbreakMe.com won't install on my iPad 3G running iOS 3.2.1. After I "Swipe to Jailbreak" it just reboots the iPad (normally) to the black Apple logo screen and then back to the desktop.
Update 2: Off to test tethering with MyWi 4.0 ($20 tethering) and IntelliScreen ($10 customizable "Slide to Unlock" screen)
Update 3: JailbreakMe has disabled MMS on my iPhone 4/4.0.1. It reportedly can be restored, but I haven't got around to testing that yet.
Update 4: If you know a Cydia app that adds a numerical dB meter in the menu bar post it in the TalkBack.