Apple released iOS 4.2.1 (final version iPhone OS ) for iPhone, iPod Touch and iPad, Apple TV Nov 22nd, 2010. It has Build – 8C148, 8C148a ; Baseband – 05.15.04 , 03.10.01, 07.10.00. This version works on ATT GSM and Verizon CDMA iPhone 4.
Major features of this release – AirPrint – Wireless printing from devices; AirPlay- wirelessly stream music and videos; Find my iPhone – locate the phone via browser; and many other fixes and enhancements.
Direct Standalone Links for iOS 4.2
- iPhone 4
- iPhone 3GS
- iPhone 3G
- Apple TV 2
- iPod Touch 2nd gen
- iPod Touch 3rd gen
- iPod Touch 4th gen
Now, before beginning make sure you have updated to iTunes 10.2.1 and downloaded the iOS 4.2.1 and saved on your desktop.
Connect the iPhone to iTunes and Upgrade to Firmware 4.2.1 for iPhone, iPod Touch ( tip: hold shift and click the update button to choose the above downloaded ipsw file ). iTunes will backup the phone first and update the firmware and restore the backup to phone.
Jailbreak iOS 4.2.1 Device on PC or MAC
- Download Greenpois0n for windows or MAC from here.
- Exit iTunes, turn off your iOS device and connect it to PC or MAC.
- Launch Greenpois0n application on computer and Click on the “prepare to jailbreak(DFU Mode)” button & wait.
- Put your device into DFU mode :
- Press and Hold the sleep button for 2 secs.
- While holding the sleep button, Press the Home button for 10 secs.
- Now release the sleep button but continue Holding the home button for about 15 secs.
- Once device is in DFU mode, you should be able to click Jailbreak button to start and will be completed.
- Once jailbreaking is done, Click the “quit” button and unplug from computer and Once your iPhone restarts – you can notice a Loader application on your Springboard.
- Launch the Loader and install Cydia and Enjoy.