How to roll back Android 12 back: 5 proven ways to roll back the system

The update to Android 12 promised revolutionary changes: a new design Material You, improved privacy and performance optimization. But what to do if the new version was slower, consumed battery power, or conflicted with critical applications? Rolling back to the previous firmware is not always a trivial task, especially if the manufacturer has blocked standard downgrade methods. In this article we will look at manual flashing via data-i="39">, as well as workarounds for devices with an unlocked bootloader. We will pay special attention to data safety - you will learn how to minimize the risk of losing photos, contacts and settings. Let us warn you right away: some methods require technical skills, but we will detail each step as much as possible.

In this article we will look at all working ways to return Android 11 or an earlier version, including official tools from Google And Samsung, manual stitching through fastboot, as well as workarounds for devices with an unlocked bootloader. We will pay special attention to data safety - you will learn how to minimize the risk of losing photos, contacts and settings. Let us warn you right away: some methods require technical skills, but we will detail each step as much as possible.

Why do users want to roll back Android 12?

According to a survey among smartphone owners Pixel, Samsung Galaxy and Xiaomi, up to 38% of users considered rolling back after updating to Android 12. Main reasons:

• 🔋 Increased battery consumption — background processes of the new version often consumed 15–25% more energy, especially on devices with 3–4 GB of RAM.
• 🐢 Slowdown of the interface — animations Material You and new transition effects required more resources, which led to lags on budget models.
• 🚫 Incompatibility of applications —some banking apps, games with anti-cheats (PUBG Mobile, Genshin Impact) or corporate software refused to work.
• 🔒 Problems with unlocking — on Samsung Knox i Pixel fingerprints or Face Unlock stopped working after the update.
• 📱 Loss of functions —manufacturers sometimes removed useful features when switching to a new version (for example, Double applications to Xiaomi).

It is interesting that on flagship devices (Galaxy S21, Pixel 6) problems were less common - their hardware is better optimized for new versions. But Owners Redmi Note 9, Galaxy A51 or Nokia 5.3 faced difficulties more often. Before you start rolling back, check if resetting the settings or disabling unnecessary Android 12 features will solve the problem.

Preparing for a rollback: what needs to be done BEFORE starting the procedure

Rolling back the firmware is not installing a regular update. There is a high risk of losing data, blocking the device, or even turning it into a brick. To avoid trouble, follow these steps:

1. Backup —a mandatory step. Android 12 changes the partition structure /data, so standard backups (for example, via Google Account) may not be restored after a rollback. Use:

• 📁 Local copy —transfer photos, videos and documents to a PC or external drive.
• 🔄 Titanium Backup (requires root)—saves applications with data.
• ☁️ Cloud services — Google Photos, Dropbox or Mega for media files.

2. Checking the model and bootloader version. Each device has its own firmware, and an error here will lead to a brick. Find out the exact model in Settings → About phone → Model. For example, SM-A525F and SM-A525M are different devices! Also check the bootloader version (fastboot getvar all) if you plan to flash via fastboot.

3. Unlocking the bootloader. On most devices (except Samsung and some Huawei), you will need to unlock bootloaderto roll back. This erases all data and may void your warranty. The instructions are different:

• 📱 Google Pixel: fastboot flashing unlock
• 🤖 Xiaomi: via Mi Unlock Tool (you need to link an account)
• 🌐 OnePlus: fastboot oem unlock

⚠️ Attention: On devices with Samsung Knox (for example, Galaxy S/Note/A series) unlocking the bootloader is triggered Knox 0x1, which permanently makes it impossible to use Samsung Pay, Secure Folder and some banking applications.

Method 1: Official rollback via OTA (only for some devices)

The safest method is to use the official rollback package from the manufacturer. Unfortunately, it is not available for all brands. Here's who supports downgrade via OTA:

Manufacturer	Supported models	Method of obtaining firmware	Data loss?
Google Pixel	Pixel 3–6 series	Via Google OTA Images	No (if you select the correct version)
Samsung	Galaxy S20/S21, Note 20 (only some regions)	Via Samsung Smart Switch or Frija	Yes (full reset)
OnePlus	OnePlus 8/9 series	Via Oxygen Updater or forum OnePlus	No
Xiaomi	Only for devices with global firmware (MIUI)	Via Mi Flash Tool (requires unlocking)	Yes

Instructions for Google Pixel (the simplest case):

1. Download the required OTA package with official website (select your model and version of Android 11).
2. Connect your phone to the PC and move the file to the root folder of the device.
3. Go to Settings → System → System update → Three dots (⋮) → Local update.
4. Select the downloaded file and confirm installation.

For Samsung the process is more complicated - you need to use the app Odin and firmware in .tar.md5format. More on this in the next section.

⚠️ Attention: If you roll back to a version older than the one with which the phone went on sale (for example, from Android 12 to Android 10 to Galaxy S21), protection may work Rollback Protectionand the device will be blocked. Check version compatibility!

Method 2: Firmware via Fastboot (for devices with an unlocked bootloader)

If the manufacturer does not provide OTA rollback packages, you will have to flash the system manually via fastboot. This method works on most devices with chipsets, but requires an unlocked bootloader and knowledge of the command line. Step 1: Install the necessary tools data-i="160">🔌 Connect the phone in Qualcomm (Pixel, OnePlus, Xiaomi, Nokia), but requires an unlocked bootloader and knowledge of the command line.

Step 1: Install the required tools

• 🖥️ Install Android SDK Platform-Tools on PC.
• 🔌Connect your phone in fastboot (hold Power + Vol Down when turning on).
• 📦 Download the factory firmware for your model (look on XDA Developers or official websites manufacturers).

Step 2: Firmware via fastboot

Unpack the archive with the firmware and run the commands in the terminal (example for Google Pixel):

fastboot flash bootloader bootloader-[filename].img
fastboot reboot-bootloader
fastboot flash radio radio-[filename].img
fastboot reboot-bootloader
fastboot flash --slot=all [firmware_name].zip
fastboot reboot

For devices with split slots (A/B), use the flag --slot=allto flash both copies of the system. It may be required. flash separately Xiaomi may need to be flashed separately vendor i system.

Step 3: First boot

After flashing, the first startup may take 10-15 minutes. Do not interrupt the process! If the phone is stuck on the logo for more than 20 minutes, try:

• 🔄 Reboot in recovery and do wipe data/factory reset.
• 🔧 Repeat the firmware, checking the integrity of the files.

⚠️ Attention: On devices with Dynamic Partition (for example, Pixel 4a and newer), incorrect firmware can damage the table sections. In this case, you will need a complete reset via fastboot -w or flashing from scratch.

What to do if fastboot does not see the device?

Make sure that the drivers are installed (for Windows - Google USB Driver). Try a different USB cable (preferably the original one). Reboot your phone fastboot again. On Linux/Mac, you may need to add rules for udev.

Method 3: Rollback to Samsung via Odin (including Knox and RMM)

Device Samsung use their own firmware system through the app Odin. The main difficulty here is bypassing the protection Knox and RMM (Remote Management), which can block the phone after downgrading.

Step 1: Preparing the firmware

• 📥 Download 4-file firmware (AP, BL, CP, CSC) for your model from sites SamMobile or Frija. It is important to choose the same version CSCthat was originally!
• 🛠️ Install Samsung USB Drivers and the app Odin3 v3.14.4.

Step 2: Firmware via Odin

1. Run Odin in administrator mode.
2. Switch the phone to mode Download Mode (press Power + Vol Down + Bixby).
3. Connect the device to the PC - in Odin a message should appear Added!.
4. Upload the firmware files into the appropriate fields:
   • BL → Bootloader
   • AP → System
   • CP → Modem
   • CSC → CSC (select HOME_CSCif you do not want to lose data)

Click Start and wait for completion (do not disconnect the cable!).

Step 3: Bypass RMM and Knox

After flashing the phone may require you to enter the old PIN code or be blocked due to RMM State: Prenormal. Solutions:

• ⏳ Wait 7 days - sometimes the lock is removed automatically.
• 🔄 Flash CSC with a full reset (CSCrather than HOME_CSC).
• 📱 Use Combination Firmware (only for experienced users!).

Method 4: Using custom firmware (LineageOS, Pixel Experience)

If official methods do not work or you want to get pure Android without the manufacturer's shells, you can install custom firmware. Popular options:

• 📱 LineageOS - lightweight and stable firmware with support for most devices.
• 🎨 Pixel Experience - ported Android with features from Google Pixel.
• ⚡ Paranoid Android —for those who like customization.

Requirements:

• 🔓 Unlocked bootloader.
• 📦 Installed custom recovery (TWRP or OrangeFox).
• 🔋 Battery charge is at least 80%.

Instructions:

1. Download the firmware and GApps (if you need Google services) from the official website.
2. Reboot into TWRP (Power + Vol Up).
3. Do Wipe → Advanced Wipe (check Dalvik, Cache, System, Data).
4. Install the firmware, then GApps, then (if necessary) Magisk for root access.
5. Reboot.

Advantages of custom firmware:

• ✅ Security updates last longer than the manufacturer.
• ✅ No bloatware (pre-installed unnecessary applications).
• ✅ Possibility of fine-tuning the interface.

⚠️ Attention: Custom firmware may not support some manufacturer functions, for example:

• 📸 Samsung Camera (photo quality deteriorates).
• 🔐 Widevine L1 (no HD in Netflix/Disney+).
• 🎮 Game Turbo on Xiaomi.

Method 5: Rollback without data loss (experimental method)

Standard rollback methods are usually erase user data. However, there are workarounds for saving information:

Method 1: Using ADB Backup

Before the rollback, create a backup via adb:

adb backup -apk -obb -shared -all -f backup.ab

After the rollback, restore the data:

adb restore backup.ab

Limitations: not all applications support this method, but some data (for example, messages in instant messengers) may not be restored.

Method 2: Transferring data via Titanium Backup (requires root)

If you already have root access, use Titanium Backup to create a complete copy of applications and their data. After a rollback:

1. Get root on the new firmware.
2. Recover data via Titanium Backup.
3. Reboot the device.

Method 3: Manual transfer via TWRP

If you are flashing through TWRP, you can manually copy the folders /data/media/0 (internal memory) and /sdcard to the PC before rolling back, and then return them back. However, system settings and application data will not be saved in this way.

Common errors and how to avoid them

Even if you strictly follow the instructions, you can encounter problems. Let's look at typical errors and their solutions:

Error	Cause	Solution
Error: Failed to boot after firmware	Incompatible firmware version or damaged files	Check the device model and download the firmware again. Flash with a full reset (fastboot -w).
Phone stuck on logo	Conflict between versions bootloader and system	Flash bootloader and radio separately, then repeat the system firmware.
RMM State: Prenormal (Samsung)	Rollback protection, triggered during downgrade	Wait 7 days or flash Combination Firmware to reset the status.
Loss IMEI or mobile network	Partition damaged modem or EFS	Restore EFS from backup or flash CP (modem) separately.
DM-Verity corruption	Incorrect firmware or changed system files	Disable dm-verity via Magisk or flash the stock one boot.img.

How to restore IMEI after an unsuccessful rollback?

If the mobile network has disappeared after the firmware, most likely the partition EFSwhere the IMEI is stored is damaged. Solutions:

• 📥 Restore EFS from a backup (if done via TWRP or ADB).
• 🔧 Use tools like ChimeraTool or Z3X (requires boxing or credits).
• 📞 Contact a service center - they can restore IMEI using a receipt or box.

⚠️ Attention: Changing IMEI manually (via the engineering menu or apps) is illegal in most countries and can lead to blocking of the device by the telecom operator.

FAQ: Answers to frequently asked questions

Is it possible to roll back Android 12 on any phone?

No, the ability to rollback depends on the manufacturer and model. For example, Google Pixel and OnePlus usually allow downgrade, and Huawei some models Xiaomi block this function at the bootloader level. Before you begin, check whether your device supports rollback.

Will the banking application work after a rollback?

It depends on the firmware. If you rolled back to the official stock firmware, problems are unlikely. However, if you installed custom firmware or received root, some banking applications (for example, SberBank Online or Tinkoff) may block work due to the trigger SafetyNet.

How to check if the bootloader is unlocked?

Turn off the phone and turn it on in fastboot (usually Power + Vol Downmode). If you see the message Unlocked or Device State: Unlockedat the bottom of the screen, the bootloader is unlocked. On Samsung check the status Knox in download mode - if Knox Warranty Void: 1the bootloader is unlocked.

Is it possible to roll back Android 12 to Android 10, skipping Android 11?

Technically it is possible, but it is extremely risky. Manufacturers often introduce protection against such “jumps” through several versions. For example, on Samsung this will lead to operation Rollback Protection, and on Pixel it may damage the partition super. It is recommended to roll back sequentially: first to Android 11, then to Android 10.

What to do if after the rollback the phone does not turn on?

If the device does not respond to buttons or is stuck on the logo:

1. Try to boot into recovery (Power + Vol Up) and do wipe data/factory reset.
2. If that doesn’t help, flash the firmware again, making sure the files are correct.
3. For Samsung try flashing Combination Firmware, then the stock firmware.
4. If nothing works, contact a service center - the memory (eMMC) may be damaged.