After the Redsn0w 0.9.9, which was a tethered jailbreak for iOS 5, an untethered jailbreak - FastRa1n v5.0 - has made its entry.
The new version of FastRa1n, released by FastUnlockiPhone.com, can make an untethered jailbreak of iPhone 4, 3GS, iPad and iPod touch on iOS 5.
To unlock these devices, you just have to run Cydia in them.
FastRa1n v5.0 is the most amazing jailbreak yet and it can unlock and jailbreak iPhone 4/3Gs 4.3.5/4.3.4/4.3.3 and the latest iOS 5, according to Joshua Hill or P0sixninja, a member of the Dev Team and a prominent figure in the jailbreak community.
Another awesome part, Jailbreak iPhone 4 iOS 5 is untethered userland jailbreak; i.e., it allows one to jailbreak iPhone 4 iOS 5 via Safari browser just like JailbreakMe 3.0.
Earlier to this, just a day after iOS 5's release, the Redsn0w jailbreak had surfaced with its new version 0.9.9 for iOS 5.
The Redsnow 0.9.9 jailbreak is a tethered one - you need a Windows or Mac computer running Redsn0w every time you reboot your iOS device.
As like FastRa1n v5.0, Redsn0w is also not able to work with the devices with the A5 processor - iPad 2 and iPhone 4S - as the processor doesn't have a bootroom-level exploit yet.
Redsn0w's new version will let you jailbreak iOS 5 on iPhone 4 all versions, iPhone 3GS, iPad one.