How to Install Android 12 on any phone: Install Android 12 GSI & Custom ROM

Introduction to Android 12 Custom ROMs

Ever since the public release of Android 12 on October 4th, 2021, the Android community has been tinkering with the source code to bring us updated Custom ROMs and ports for various devices.

If you don’t have a Pixel device or a top/flagship Android Phone, the OTA update for Android 12 is not coming for your device any time soon. But, the Custom ROMs are here to save us. Here are some devices for which Android 12 based Custom ROMs/ports have been released and the guide to installing it.

List of devices with Android 12 Custom ROMs:

• ASUS ZenFone Max Pro M1
• Lenovo Z6 Pro
• Moto G9 Plus
• Nokia 6.1
• Nokia 6.1 Plus
• Nokia 7 Plus
• Nokia 7.1
• OnePlus 5
• Samsung Galaxy Note 10, Galaxy Note 10+, and Galaxy Note 10+ 5G
• Samsung Galaxy S10e, Galaxy S10, and Galaxy S10+
• Mi 11 Lite 4G
• Mi A1
• POCO F1
• POCO X2/Redmi K30
• POCO X3
• POCO X3 Pro
• Redmi 5 Plus/Redmi Note 5
• Redmi K20 Pro/Mi 9T Pro
• Redmi Note 8 and Redmi Note 8T
• Redmi Note 10
• Redmi Note 10 Pro and Redmi Note 10 Pro Max
• Redmi S2/Y2

Prerequisites:

• Make sure that uour PC has adb and fastboot installed.
• Make sure that you have USB Debugging enabled in your Android device under Developer Options.
• Latest firmware for your device flashed.

Unlocking the bootloader:

Warning: This process will erase all data on your device. Be sure to backup all your important data to your PC before proceeding.

Note: Some OEMs have different and specific methods for unlocking the bootloader.

1. Enable OEM unlock in Developer Options, if present.
2. Connect the device to your PC via USB. Note: Type adb devices in the command prompt to check if your device is connected and adb is working.
3. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type: adb reboot bootloader . You can also use the combination Volume Up + Power Button to boot into fastboot mode.
4. Once the device is in fastboot mode, verify your PC finds it by typing: fastboot devices
5. Now, to unlock the device type: fastboot oem unlock
6. If the device doesn’t automatically reboot, reboot it. It should now be unlocked.
7. Since the device resets completely, you will need to re-enable USB Debugging to continue.

Installing a Custom Recovery:

1. Goto the TWRP website and download the custom recovery image for your device. Optionally a different custom recovery imaage can be accquired for a device from XDA, if present.
2. Make sure to enable USB Debugging under Developer Options. To enable Developer Options then Go to System Settings > About Phone then under About Phone section tap Build Number ten times straight. If you are on MIUI devices then tap MIUI Version ten times until you see a message ” No need you are already a Developer “
3. Connect the device to your PC via USB. Note: Type adb devices in the command prompt to check if your device is connected and adb is working.
4. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type: adb reboot bootloader . You can also use the combination Volume Up + Power Button to boot into fastboot mode.
5. Once the device is in fastboot mode, verify your PC finds it by typing: fastboot devices
6. To flash the custom recovery to the phone, type: fastboot flash recovery path/to/the/recovery/image/file
7. After the flashing has completed, boot in recovery mode by typing: fastboot boot recovery
8. Now boot into the system from the custom recovery.

Note: If you are coming from stock ROM, do not reboot into the system directly, or else the custom recovery may not persist.

If you didn’t understand then watch this video to know the detailed process of installing TWRP on a phone. I will update a more convenient method with the Minimal ADB Fastboot Tool.

Installing the Android 12 Custom ROM:

1. Download an Android 12 based Custom ROM or a port for your device from the list above and place it in the internal storage or SD Card.
2. Most of the Android 12 ROMs are currently vanilla so it is advised to download a seperate gapps package from OpenGApps, NikGApps or any other gapps recommened by the Custom ROM. Place it in the same location as the Custom ROM package.
3. Boot into recovery by holding Volume Down + Power
4. Now is the time to take a complete backup of your device, in case if anything goes wrong.
5. In recovery, wipe Dalvik Cache/Cache, System, Data.
6. Now go to install section and from the file manager select your Custom ROM packgae and flash it.
7. Then Select the GApps package and flash it next.
8. If everything went fine, you can boot into the system now.
9. Booting into the system for the first time after flashing may take some time, so have a little patience.
10. Enjoy the latest and gratest Android 12.
11. You can additionally flash Disable DM Verity File and Magisk before booting into OS.

Note: Android 12 builds are mostly in the beta stage. Be ready for bugs.

Note: If the device does not boot properly or goes into a bootloop, try force rebooting it by pressing and holding down the Power button. If nothing works, boot into recovery and restore the stock android backup.

Note: Some devices may have a very specific way of installing a Custom ROM. Be sure to read the information on the Custom ROM page.

Note: The builds may require a specific Custom Recovery or a specific version of it. Be sure to read the instructions on the Custom ROM page.