ALPHA-ONE Factory Reset
Factory reset won’t delete your google account history.
This Factory reset recommended when you forget lock pattern and passwords.
Reset the phone to factory default settings.
All data in the internal storage is erased include google account history.
1.From the home screen open 'Settings'
2.After that select 'Backup&Reset' and tap Factory data reset
3.Choose Reset phone and select Erase everything to begin hard reset operation