How to save Android before flashing: a complete guide

The process of flashing a device based on an operating system Android is often associated with completely erasing all user data. This is an inevitable stage if you are planning to switch to custom firmware, change the region, or restore the brick. However, many users underestimate the risks of losing personal information until they are faced with empty internal storage after a reboot.

Preparing for the procedure requires not just copying files, but creating a comprehensive backup, including settings, passwords and folder structure. In this material, we will look at all available ways to save content: from cloud services to advanced PC tools.

Ignoring the backup step can lead to the irretrievable loss of important documents and photos. Even if you use automatic synchronization, manually checking the integrity of the archives before manipulating the system partition is a mandatory rule of digital hygiene.

Synchronization with a Google account

The simplest and most accessible method of saving basic data is using the built-in ecosystem mechanisms Google. This approach does not require connecting to a computer and installing additional software, however, it has its limitations in terms of the amount of information stored.

To activate the function, you must go to the device settings and select a section Accounts and synchronization. Here you should make sure that the switches next to Contacts, Calendar and Notes are active. The system will automatically upload this data to the cloud, linking it to your Google ID.

⚠️ Attention: Contact synchronization does not always save profile photos and additional numbers written in non-standard fields. Always check the upload via the web interface contacts.google.com.

Particular attention should be paid to backing up application data and system settings. In the menu System → Backup you can initiate a forced upload of Wi-Fi network configurations, call history and a list of installed apps. This will allow you to quickly restore your working environment after installing the new firmware.

Backup multimedia to PC

Photos, videos and documents take up the lion’s share of the smartphone’s internal memory. Cloud storage often has limits on free space, so transferring heavy files to your computer's hard drive remains the most reliable solution.

Connect your device to your PC using the original USB cable. On the smartphone screen, in the connection notification, select the operating mode File transfer (MTP). After this, your phone’s drive will be displayed in the computer explorer.

Copy the following key directories to save everything important:

• 📁 DCIM —all pictures from the main camera and screenshots are stored here.
• 🎵 Music and Download — folders with downloaded music and documents from the browser.
• 💬 WhatsApp/Media —if you use instant messenger, here are the received images and voice messages.

The process of copying large amounts of data can take considerable time. Do not interrupt the connection and make sure that the smartphone screen does not go completely dark if the drivers are unstable. After the operation is completed, it is recommended to compare the size of the folders on the source and destination for verification.

Creating a full system image (Nandroid Backup)

For users planning to install custom firmware or obtain root-rights, standard methods for copying files are not enough. A critically important step is to create a complete snapshot of the system, known as Nandroid backup.

This procedure is only possible if you have a custom recovery installed, such as TWRP or OrangeFox. The image saves absolutely all memory sections, including system, boot and data, allowing you to roll back to the previous state in one click.

The algorithm of actions in recovery mode is as follows:

1. Boot into mode Recoveryby holding down the combination of the power and volume keys.
2. In the menu recovery select item Backup.
3. Tick the sections System, Data, Boot and EFS.
4. Swipe the slider to start creating the archive.

⚠️ Attention: Section EFS contains unique identifiers of your modem (IMEI). Losing this partition due to unsuccessful firmware may result in the inability to work with the cellular network. Make sure that it is included in the backup.

The finished archive is usually saved to internal memory or to an SD card in a folder TWRP/Backups. It is strongly recommended that you copy this heavy file to your computer immediately after creation, since formatting the data will clear the internal storage.

What to do if there is no custom recovery?

If you have a stock bootloader and do not have TWRP, you cannot create a full system image using standard tools. In this case, rely on Google syncing and manually copying the files to your PC. Attempts to unlock the bootloader to install recovery themselves erase the data.

Saving application and instant messenger data

Many users are faced with a situation where, after flashing the firmware, applications are reinstalled, but the entire history of correspondence and progress in games disappears. Standard Google synchronization does not always correctly process local messenger databases.

For WhatsApp and Telegram you must use the built-in export functions. In the chat settings, select creating a local copy or sending an archive to Google Drive. For Telegram, it is important to check if the cloud storage option is enabled, since secret chats are only stored on the device.

Games and specific applications often store progress in the Android/obb or Android/datafolder. These directories are not always included in the standard backup. Use a file manager with access rights to these hidden folders to manually copy them before resetting.

Data type	Save method	Risk of loss
Contact	Google Sync	Low
Photo/Video	Copying to PC	Low
System settings	Google Backup / ADB	Medium
Secret chats	Manual export is not possible	High

Using the ADB utility for advanced users

Toolkit Android Debug Bridge (ADB) provides backup capabilities not available through the GUI. This method allows you to unload application data along with their cache and settings without the need for root access.

You must first activate the mode USB debugging in the menu For developers. After connecting your smartphone to the PC, run the command in the terminal or command line to start the backup process.

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

A request to confirm the creation of a backup copy will appear on the device screen. Enter the password to encrypt the archive (or leave the field blank) and click the confirm button. The process may take a long time depending on the volume of data.

Data recovery is performed with the command adb restore backup.ab. It is worth noting that some application developers block the ability to backup their products via ADB for security reasons, so the method is not a universal solution for all apps.

Final check and preparation for firmware

Before proceeding with the actual installation of new firmware, it is necessary to audit the saved data. Make sure that critical files are accessible not only on your phone, but also on external storage or in the cloud.

Check your device's battery charge. The flashing process is energy-intensive, and a sudden power outage in the middle of writing a system partition can result in severe boot errors. It is advisable to have at least 60-70% charge.

⚠️ Attention: Menu interfaces and item names may differ depending on the version of Android and the manufacturer’s shell (MIUI, OneUI, ColorOS). Always check the official documentation for your specific model before formatting.

Disable any security locks such as FRP (Google Lock) by deleting accounts from settings before resetting. This will prevent a situation where, after flashing the firmware, the phone asks for a password from the previous account, access to which has been lost.

Frequently asked questions (FAQ)

Will firmware erase data on an SD card?

Usually the standard firmware procedure affects only the internal memory of the device. The data on the external memory card remains intact. However, if you use the “Format as internal storage” function, the card will be encrypted and tied to a specific system, so access to it after a reset may be lost without decryption.

Is it possible to recover data without a backup?

The chances are extremely low. After formatting the partition userdata the file system marks the sectors as free. Specialized data recovery software can only help if no new data was written over the deleted information, but in the case of firmware, a new system is written, which makes recovery almost impossible.

Do you need to delete your Google account before flashing the firmware?

Yes, this is highly recommended. The FRP (Factory Reset Protection) protection mechanism requires entering the password from the last synchronized account after the reset. If you forget your password or lose access to your mail, it will be very difficult to unlock your device.

How long does it take to create a Nandroid backup?

The time depends on the amount of space used and the speed of the memory card. On average, the process takes from 5 to 15 minutes. Do not interrupt it, even if the screen goes dark - the recovery continues to work in the background.