Hello friends, Please help me.
I was trying to change my os from 2.3.6 to os 4 something but the file i installed from the recovery mode was corrupted. My phone has the new os but the sim card, camera, bluetooth, sdcard and the lock screen won't work. I want to take it back to what it was. can anyone help me how?? I don't even have the back up.
Please help me.

And other question.
I have two phones gt-s5302
can i back up the os of one phone and install it to the other??
how??
With which tool??
Please help!!