In order to hard reset a Cube U35GT Quad, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Cube U35GT Quad device will be brought back to the default configuration of a brand new device.
1. Press'n'hold the Power button until the phone turns on.
2. Now open Menu and select Settings > Backup & Reset > Factory data reset > Reset Phone > Erase Everything.
3. Wait for your phone reset and restart. Done! Hard reset is now complete.