Apart from iOS 4.2.1 for iPhone, iPad and iPod touch, also released today is iOS 4.2 for Apple TV 2G which brings video AirPlay feature that will allow you to stream pictures, videos and music right from your iPhone, iPad or iPod touch to TVs connected to the second-gen Apple TV.
Apple has just released the very final version of iOS 4.2.1 for iPhone 4, iPhone 3GS, iPhone 3G, iPad and iPod touches. This version of iOS brings a number of new features for iPhone, iPad and iPod touch users including: Multitasking, Folders and Game Center for iPad, AirPrint, AirPlay, and other system wide changes and improvements.
The recently released Redsn0w 0.9.6b3 can jailbreak all iOS based devices including the new A4 devices like iPhone 4, iPad and iPod touch 4G. Since Cydia included in this version of Redsn0w is not compatible with iOS 4.2.1, you can use the following steps to install a patched version of Cydia.
Since Cydia is broken on iOS 4.2.x, the new Redsn0w 0.9.6b3 released today supports iOS 4.2.1 so that developers can make their jailbreak-apps compatible before Apple releases the final firmware to public. Using this version of Redsn0w, you can now install jailbreak-apps without using Cydia.
PwnageTool bundle for iPod touch 4G on iOS 4.2.1 GM has just been released. You can use this bundle with existing version of PwnageTool to create custom firmware file which is jailbroken on the newly released iOS 4.2.1.
Device Speed Test is a new app available in Cydia which lets you test the speed and efficiency of your iPhone, iPad or iPod touch, whilst also recommending what you should do to improve performance in simple ways.
Thanks to a new tweak available in Cydia, iPhone brightness can now be adjusted from the multitasking tray, found just under the music controls with App Switcher Brightness.
iOS 4.2.1 was released yesterday for iPhone 4, 3GS, 3G, iPod touch 4G, 3G, 2G and iPad. Even though iOS 4.2.1 jailbreak is possible via Redsn0w 0.9.6b2, but Cydia is still broken which makes the jailbreak pointless for many. It also contains new baseband for all iOS devices which currently makes it impossible to unlock using existing version of Ultrasn0w. So if you upgraded to iOS 4.2.1 and now want to downgrade back to iOS 4.1 / 4.0.2 / 4.0.1, follow the instructions posted below to downgrade iOS 4.2 on iPhone 4, 3GS, 3G, iPod touch and iPad to iOS 4.1 / 4.0.x.
Alright guys, here is a quick heads up! Apple has seeded iOS 4.2.1 GM to developers hinting towards the fact that final version will see the light of day soon. If you’re one of those who are currently relying on a jailbreak or a carrier unlock then we highly recommend that you avoid updating to iOS 4.2.1.
After releasing a revised version of iOS 4.2 GM for iPad to developers last week, Apple has now seeded iOS 4.2.1 GM for iPhones, iPad and iPod touches. This build is meant for developers only. Only members enrolled in the iPhone Developer Standard or Enterprise Program can access these bits of by signing into Apple Developer Connection.

