I had a very suprising when i experience this with my friends itel android phone,he entered the wrong pattern on his phone sevral time and the phone got locked.
when i got the phone i tried all sort of hard reset that i know,holding the: Power bottom a nd the volume+ simultaneously but nothing to display.
But now holding d the volume- key i.e volume down key and continues holding them till it display the recover mode.
First you will switch of your Android device. After switching it off your android device, press your volume down key.
Now press the power button and hold it too along. It will start a secret terminal interface.
Select the option and wait Your device will take some few minute after finish it will restart and you will find out your android device has been unlocked.
Enjoy and share this to your friends via facebook and twitter together with google plus.
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