How to Root Sony Xperia Ion, Android Rom Updates

First download the insecure kernel from here and choose the file that suits your OS.
Then, download the root package from here.
Also download fastboot file from here.
All these files must be saved on your computer.
Extract fastboot in C:/ drive.
Turn off the handset and enter the same in fastboot mode.
For this press and hold Volume UP button while powering on.
In fastboot mode connect the Ion with the computer.
On the PC open command prompt by selecting “start -> all programs -> accessories -> right click on command prompt and choose run as administrator”.
On the cmd window type: “fastboot flash boot filename.elf”.
Filename must be replaced with the name of the insecure kernel you had downloaded before.
Now, disconnect and reboot the device.
On the PC extract the root package.
Connect the smartphone again with the computer.
On the PC run the batch file (the .bat one) and wait while your device is being rooted.
In the end, unplug the USB cord.
And go to Google Play and download Superuser and BusyBox apps.