Pattern lock is most secure screen lock for Android device, but What do you do if you have forgotten your unlock pattern or password on your Android device?
In this case you have following options:
1) Give Google Account Username and Password
After five times unsuccessful attempt, you can see another option named “Forgot pattern“. While pressing forgot pattern you can see a window asking your email address and password with which you registered your android device. Give these details here and now you can see the option to reset your pattern lock.
2) Factory Reset
If you forgot your Google account password too and try to recover it on Internet. But unfortunately you unable to recover it, then last option is factory reset.
To do factory reset here are the steps –
Power off your device.
Press Volume UP+Home+Power button at a time till Samsung logo appears. (For HTC One: VolumeDown+Power, For Google Nexus 4: VolumeDown+Power)
This enters Recovery mode of Android device.
Select the option “Wipe Data/ Factory Reset” by using volume up and down key.
After conformation it will delete all user data on device and you can set again lock pattern.