Unlock your Vivo Y91 3GB RAM

OS: Android v8.1 (Oreo)

CPU: Snapdragon 439

RAM: 3 GB

Display: 6.22 inches

Camera: 13 MP 2 MP

Battery: 4030 mAh

1. Use the Tenorshare 4uKey for Android app.
2. Make a hard reset (factory reset).
3. How to use a low battery to unlock a phone locked with a graphic key.
4. Delete 'gesture.key' and 'password.key' using Aroma File Manager.
5. Restore access to your smartphone using your Google Account.

1. Use the Tenorshare 4uKey for Android app.

Connect your phone to PC and launch Tenorshare 4uKey for Android.
In the menu that appears on the PC screen, click Remove.
fter verifying the data, the removal of the smartphone screen lock will begin. Confirm the deletion, click OK.
Wait until the end of the operation, and put the phone into recovery mode.
Click the Next button, then follow the steps recommended by the program to restore the device to factory settings and reboot it. After rebooting the smartphone, the screen lock will be disabled.

2. Make a hard reset (factory reset)

To get started, turn off your smartphone.Simultaneously press and hold for about 10-15 seconds one of the button combinations:
Volume down button + Power button;
Volume up button + Power button;
Volume down button + Power button + Home button;
Volume down button + Volume up button + Power button.
Select Recovery by using the volume buttons to move through the menu and confirm the selection by pressing the power button.
Select Wipe data/factory reset. by using the volume up/down buttons to move through the menu and confirm the selection by pressing the power button.
At the end, confirm the reset operation.

3. How to use a low battery to unlock a phone locked with a graphic key.

You need to ensure that the phone battery is discharged. To speed up the process, make sure that the screen is constantly lit.
When the battery has a few percent left, the phone will report this and open a menu with power settings, that is, it will unlock the phone.
You need to quickly find the page with security settings in the menu and disable the lock.

4. Delete 'gesture.key' and 'password.key' using Aroma File Manager.

Turn off your phone and prepare a memory card.
Copy the Aroma File Manager program to the phone's memory card. Insert the memory card back into the phone.
Put your smartphone into recovery mode using the button combinations that are suitable for your particular model.
In recovery mode, select the Install zip option. Then select Install zip from sdcard, Choose zip from sdcard, go to the archive folder with this program and select it.
You need to go to the /data/system folder and delete the files 'gesture.key' and 'password.key' (for the Android 4.4 or lower operating system) or 'getekeeper.password.key' and 'getekeeper.pattern. key' (for Android 5 operating system or higher)
Reboot your device.

5. Restore access to your smartphone using your Google Account.

When you try to unlock the phone several times, Forgot password? will appear on the screen. Click on it.
You will be asked to enter your Google Account username and password.
Remove the screen lock from the settings.

Thomas Nilan
Smartphone Expert

Thomas Nilan is a mobile phone expert with in-depth knowledge of the Android and iOS operating systems, who understands the settings of various hidden features that allow you to expand the capabilities of your smartphone, as well as get information about what is going on inside the phone for future repairs. He is an authority in his field, which has allowed him to become a ghostwriter for several technology publications, and he enjoys writing small mobile applications for testing smartphones.