Here an one-click application to install Superuser and su binary on phone. Look at the compatibility list here to see if this application can be useful for you.
Feedbacks on supported devices will be greatly appreciated in order to update the compatibility list. Post your feedback here
Superuser and su binary include in application work from android 2 to 4.
!! Important !!
Success with this application void warranty on your device.
If you need help, read the FAQ first before posting your question in the help thread
If you like my work, you can buy Framaroot donation app
Many many thanks to all donors
Download it on your device (links are available at the end of this post)
Install it with a file explorer or directly from your internet browser, if android warn you about security risk, say OK and check Unknown sources to allow install of applications outside of Play Store.