These are instructions on how to jailbreak your iPhone 4 on the 4.3.1 firmware using RedSn0w.

Make sure not to update to iOS 4.3.1 if you need an unlock as one is not yet available!

Step 1 – Create a folder on your desktop called Pwnage
Download RedSn0w from here and place it in the Pwnage folder. Likewise, download the latest 4.3.1 firmware from below and place it in the same folder.

4.3.1 (4 GSM): iPhone3,1_4.3.1_8G4_Restore.ipsw

Extract the RedSn0w zip file into the same folder.

Step 2 – Connect your iPhone to the computer and launch iTunes.
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These are instructions on how to jailbreak your iPhone 3GS on the 4.3.1 firmware using RedSn0w for Windows.

Make sure not to update to iOS 4.3.1 if you need an unlock as one is not yet available unless you opt to use the iPad baseband.

IMPORTANT FOR UNLOCKERS
During this process you can update your baseband to the 06.15 version. If you are on 05.14 or 05.15 or higher you will need to do this to unlock. You do not need to do this for jailbreak only. Please read the following very carefully before deciding whether to do this.
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These are instructions on how to watch Flash video on your iPhone, iPad, or iPod touch using the iOSFlashVideo bookmarklet. Currently support sites are Dailymotion, Flickr Video, MegaVideo, Vimeo.

1 – Press to launch Safari from your SpringBoard.
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Some users have reported poor performance after the update to iOS 4.2.1. These users report delays in opening apps, switching between apps. They also report that the keyboard is slow to appear when beginning to enter text.

Fixes

Perform a “hard reset : ” Hold down the sleep/wake and home buttons simultaneously for roughly 15-20 seconds, until the screen powers off then an Apple logo appears, which signifies a reboot. Some users have (oddly enough) reported that performing two hard resets resolves the slowness issue.

Restore, but not from backup : It appears that bad holdover data from iPhone backups can cause performance problems. Restoring as a new phone will delete contacts and other data, but may resolve this issue.

To do so, connect your iPhone or iPod touch to your computer, click “Restore” in iTunes, then choose “setup as new phone.”
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