Jailbreak iPhone IOS 4.2.1 with GreenPoison RC5 Untethered
Well we already knows that GreenPoison RC5 has been released. It is Untethered version of Jailbreak for iPhone IOS 4.2.1 and further on it can be Unlockable as well. For iPhone IOS 4.3 Jailbreak we have to wait for the iPhone IOS 4.3 to release adn so far, iPhone 4 will get the advantages of GreenPoison RC5 only because this particular version is only released for the iPhone 4, 3GS, iPod 2G, 3G abnd 4G and iPhone IOS 4.2.1, iPad and Apple TV but still it is Untethered.
Here is the simple guide through which your iPhone device will be jailbreak easily.
Here you go with the procedure of Jailbreak iPhone IOS 4.2.1:
Process of iPhone IOS 4.2.1 Jailbreak
1. First Download GreenPoison RC5 and Run it.
2. Follow the instruction, where you will be asked to put your device on DFU mode (we expect and assume that user to be known with DFU mode).
3. After the device is in DFU mode, GreenPoison will start the jailbreak process and once it is done, your home screen will show the loader and you can install cydia via it.
Thats it You are done with Jailbreak iPhone IOS 4.2.1 Untethered.
For Video Step by Step Guide follow the Crunchitech.com where for MAC users how guide is also elaborated.