By reading this tutorial I got from xda developer forum, I provide you the way how to root your EVO 3D and Sensation device. Read the full story below:



What is Fre3vo: Fre3vo is a temp-root acquiring tool, allowing users access to a root shell on their HTC EVO 3D and Sensation devices.

What is Fre3dom: Fre3dom is the name of the tool being developed to enable S-OFF on the EVO 3D and Sensation.

ETAs:
Fre3vo: Available Now!!! http://tinyw.in/1lJ
Fre3dom: No ETA yet.

Prereqs:
1. You must be able to push files via adb to your device.
2. You must know what a shell is.

Instructions:
1. Download the fre3vo zip
2. Unzip the fre3vo binary
3. Push the binary via 'adb push fre3vo /data/local/tmp'
4. Change the permissions via 'adb shell chmod 777 /data/local/tmp/fre3vo'
5. Run the binary via 'adb shell /data/local/tmp/fre3vo'

If all goes well, you'll be kicked back to your computer's command prompt. (Some may get more messages, but it seems the Sensation buffers the stderr more than the EVO 3D)

run 'adb shell' and you should have a '#' prompt instead of '%'.

This is temporary root. A reboot will clobber it. Also realize that the system partition is nand-protected (at least on the EVO 3D) so writes won't stick for long, and there will be issues getting tools like Titanium Backup to work. We are still developing upon this huge stepping stone. We look forward to hearing methods other developers have found to build temp root to either make the device better, or gain perm root even.

This *IS* a work in progress.

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