[EVO 4G Android Development] taverentech:
Simply speaking, root, is same as Administrator on Windows, aka SuperUser. On Unix operating systems, root is the 'god' account. Sprint/Verizon/AT&T all sell there phones unrooted. This is so users cannot change the operating system and default installation applications and to disable some functionality of Android system. Sprint and others want you to pay extra for WiFi tethering... which I think is rediculous because that is a function of the phone, not Sprint. And its not like you're stealing from Sprint because you're paying for data (I even have to pay the $10 premium data charge and I don't get 4G where I live). Plus, in my case I didn't buy my phone from Sprint, which I think gives me a little more ethical room to wiggle.

Using SimpleRoot OTA 1.47.651.1 Edition, GUI is probably the easiest and best way to do this. However, its not just steps 1,2,3. You also might have to install update su program, which requires installing one of the recovery programs under extras first. Then you have to install wireless tether for root users (best one out there)... though market version is old, I downloaded and manually installed wireless_tether_2_0_5-pre4.apk. Installing apk is easy, you just copy it to your sdcard, then using file manager (I use adwexplorer) open that apk and it will install like you would from market.

Then, once you root your phone, you never ever want to do an OTA update (via sprint) because if the techies can't find a way to regain root, you'll never have control of your phones full set of features when sprint doesn't want you to. Example, Verizon was so bad when I upgraded to a media phone a few years ago I was pissed that I couldn't play my own mp3s off the sdcard without paying monthly mp3 service fee... It was my phone, my sdcard, and my mp3s I copied onto my phone.... that's when I left Verizon. Plus E&W starting at 9pm, and charging extra for visual voicemail.

Sprint isn't currently that bad, but you never know, although calling voicemail between 7a-7p counts as anytime minutes, wtf! If you use visual voicemail, that is data (which is unlimited for me).

Summary, install SimpleRoot OTA 1.47.651.1 Edition, GUI , go through the three steps,, carefully, do not rush it. Then under extras install recovery program, I use clockworks. Then, install wireless_tether_2_0_5-pre4.apk.

See if there is an application installed called SuperUser... if yes use that first, then wifi tether. If not, you need to put su-2.1-e-unsecure-signed.zip on the root of your sdcard... boot into recover (power on, volume down), go to install zip from sdcard, select su-2.1-e-unsecure-signed, run update. Again, this is what *I* did... and su-2.1-e-unsecure-signed may not be needed, perhaps I got some of the instructions mixed in, but I have working wireless tethering and I'm happy.

BTW, its recommended that you go into recovery once and do a nand backup... having a backup of working system on your sdcard PRIOR to attempting any future updates of ROM or anything else is highly recommended... even if you screw up your phone, someone who knows how will be able to help you recover only if you have functional backup and functional recovery app.