iPhone Dev-team updated their PwnageTool and redsn0w programs to jailbreak iOS 4.3.3 using Mac and Windows in a way that doesn't require connecting the device to a computer each time it's rebooted.
The iOS 4.3.3 untethered jailbreak is based on the exploit created by @i0nic for iOS 4.3.1. The updated redsn0w tool also allows you to turn on multitasking gestures, dev team noted in a blog post. If you wish to unlock your device for use with any carrier, there's an app for that.
To unlock an iOS 4.3.3 device, use the ultrasn0w tool. Remember that ultrasn0w at the time of this writing only worked with iPhone 4 baseband 1.59.00 and iPhone 3G/3GS basebands 4.26.08, 5.11.07, 5.12.01, 5.13.04 and 6.15.00. Use a custom IPSW to update to 4.3.3 in order to avoid updating your baseband. You may wanna use excellent ipswDownloader for Mac to easily find and download any iOS firmware build. This app also figures out your baseband version and tells you whether your iOS version can be jailbroken and unlocked. If you're on Windows, download the f0recast app that checks whether your device is unlockable or tethered with a USB connect.
If you just want to perform an untethered iOS 4.3.3 jailbreak, it's recommend handy step-by-step guides for redsn0w or PwnageTool. The below video shows how easy it is to perform an untethered jailbreak of iOS 4.3.3 via redsn0w 0.9.6rc15.
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