If your phone doesn't want to boot up again after the update, it gets stuck in a black screen, follow this tutorial where we root the Galaxy SII with Odin and put an official Samsung Android 4 ICS on it.
Let me show you how to set up a Wi-Fi hotspot on Nokia Lumia 920 and other Windows Phone 8 devices so you can share the Internet to other Wi-Fi enabled devices.
If you are on a certain data plan on your mobile provider, and don't want to exceed it, you can set data usage warning and a limit which can help you save some of your money.
Let me show you how simple is is to turn your Samsung Galaxy S3 into a wireless hotpot you then connect to with any other WiFi device and surf the Internet.