How to access Recovery mode?
Can I downgrade my phone to the lower Android version?
Where can I download ROM or firmware for my phone?
How to downgrade my phone?
How to flash the firmware?
How to unlock Bootloader(BL)?
Can I install the firmware of other phones in my vivo phone?
Is there an international firmware for the phones such as X21 sold in Chinese Mainland?
How to exit the Fastboot mode?
It prompts "Decryption unsuccessful" while installing the firmware. What should I do?