How to install a new operating system on Android

Installing a new operating system on a device with a logo Android is a process that goes far beyond a simple over-the-air update. Many users decide to take this step when the manufacturer stops supporting the model or when the standard interface no longer meets the needs for speed and functionality. Custom firmware can give your gadget a second life by providing access to the latest versions of the OS even on outdated hardware.

However, it is worth understanding that intervention in The system partition carries serious risks. Wrong actions can turn a modern smartphone into a useless piece of plastic, known in the community as “brick”. Before starting any manipulations, it is critically important to realize that you are acting at your own peril and risk, and the warranty on the device will most likely be voided instantly.

The question of expediency is often especially acute: is it worth spending time on reflashing for the sake of a couple of new functions? If your phone is stable, it may be better to limit yourself to optimizing the current system. But if the battery “dies” in a couple of hours, and the interface slows down even in simple menus, then custom ROM becomes the only reasonable solution to extend the life of the device.

⚠️ Attention: The procedure for installing a new OS irreversibly erases all user data. Make sure you have created a complete backup of your contacts, photos and documents in cloud storage or on your computer before starting work.

Preparatory stage and firmware selection

The first and most important step is to find the right software. The Internet is filled with thousands of builds, but not all of them are safe or stable. You need to find firmware designed specifically for the code name of your device model. Using an image from another smartphone, even if they look the same, is guaranteed to lead to the inoperability of radio module or the touchscreen.

The forum is considered the most authoritative source in the world of modding. It is there that enthusiasts publish their work, indicating the current status of the project: “Stable version”, “Beta” or “Alpha”. For everyday use, it is recommended to choose only stable builds marked as XDA Developers. It is there that enthusiasts publish their work, indicating the current status of the project: “Stable version”, “Beta” or “Alpha”. For everyday use, it is recommended to select only stable builds marked as Stableas they have been sufficiently tested by the community.

In addition to the firmware itself, you will need a specialized recovery menu that replaces the standard recovery. The most popular solution is TWRP (Team Win Recovery Project). It allows you to install unsigned system images, create full partition backups System and clear the cache before installation.

Also do not forget to download the necessary drivers for your PC. For processor-based devices Qualcomm often you need specific ones, without which the computer simply will not see the phone in bootloader mode. Lack of the correct driver is the most common reason why the process freezes at the connection stage. ADB and Fastboot drivers, without which the computer simply will not see the phone in bootloader mode. Lack of the correct driver is the most common reason why a process hangs at the connection stage.

Unlocking the bootloader

Smartphone manufacturers block the bootloader by default to prevent the installation of uncertified software. This is a security mechanism that verifies the digital signature of the system every time it is turned on. To install a new OS, this protection must be removed. The unlocking process differs depending on the brand: for Xiaomi requires waiting for several days through the official utility, and for Google Pixel or OnePlus the procedure takes a couple of minutes.

In most cases, unlocking is performed through the mode Fastboot. You need to connect the switched off phone to the computer, hold down a certain combination of buttons (usually volume down and power) and enter the command in the terminal. After successful execution of the command, the bootloader will enter the Unlockedstate, which will be indicated by a warning message every time the device starts.

You should remember that unlocking the bootloader triggers the security mechanism Android, known as Verified Boot. This may cause some banking applications and services to stop working because they consider the system to be compromised. You can bypass this limitation using a utility Google Pay will stop working because they consider the system to be compromised. You can bypass this limitation using the utility Magiskthat hides the fact that you have obtained superuser rights.

What is OEM unlocking?

This is an item in the “For Developers” menu that must be activated BEFORE entering commands in Fastboot. If this switch is turned off, the unlock command will be rejected by the device with an error.

After unlocking, all data on the internal storage will be permanently deleted for security purposes. This is standard practice to prevent data theft by attackers who gain access to the bootloader. Therefore, a repeated reminder about backup is more relevant than ever here.

Installing custom recovery (TWRP)

The stock Android recovery menu has extremely limited functionality: it only allows you to reset to factory settings or apply an update from the manufacturer. To install a third-party OS, we need a tool with advanced capabilities that can mount partitions and work with archives .zip. The leader in this niche has remained for many years TWRP.

The TWRP installation process usually occurs through a computer using the command fastboot flash recovery twrp.img. It is important to prevent the phone from being rebooted into the system immediately after flashing the recovery firmware, otherwise the standard bootloader may overwrite the new image with its standard counterpart. The correct sequence of actions involves immediately entering recovery mode manually by holding the volume and power buttons.

Inside the TWRP menu, the interface is intuitive even for beginners. You will see large buttons for basic actions: Install (Installation), Wipe (Cleaning), Backup (Backup). Before flashing a new system, it is highly recommended to make a full backup of the current firmware (Nandroid backup). This will save you if the new OS turns out to be inoperative or causes critical errors.

Some modern devices use dynamic partitions or system A/B partitioning, which complicates the installation of classic TWRP. In such cases, it may be necessary to use temporary recovery, which is loaded into RAM by the command fastboot boot twrp.img, without permanent recording to flash memory.

The process of installing a new operating system

When all the preparatory stages have been completed, the most crucial moment comes - the actual installation of the new system. The firmware file (usually an archive .zip) must be placed in the internal memory of the device or on an external drive connected via OTG. In the TWRP menu, select Install and find the downloaded archive.

Before installing a new system, you must perform a complete data wipe to avoid file conflicts and operational errors. In the section Wipe select Advanced Wipe and tick the sections Dalvik / ART Cache, System, Data and Cache. The section Internal Storage does not need to be touched if the firmware file is located there.

After cleaning, swipe the slider to confirm the installation. The process will take from a few minutes to half an hour depending on the speed of the memory and the size of the firmware. In the installation log you will see technical messages about mounting partitions and unpacking files. When the process is complete, a button will appear Reboot System.

Memory section	Purpose	Need to clean?
System	Operating system files	Yes, definitely
Data	Custom applications and settings	Yes, required
Cache	Temporary system files	Yes, desirable
Dalvik/ART	Application optimization cache	Yes, required
Internal Storage	Photos, music, documents	No (if there is firmware)

The first launch after installation can take a significant amount of time - from 5 to 15 minutes. At this moment, the system optimizes applications and creates new configuration files. Don't panic if the phone hangs on the logo for a long time Android, this is normal behavior during the first boot.

Installing drivers and add-ons (GApps)

Most custom firmwares are delivered in a “pure” form, without pre-installed services Google. This is done for privacy reasons and to reduce image size. However, for most applications to work fully, you will need to install the package GApps (Google Apps). You need to download it in advance, strictly observing the compliance of the Android version and the processor architecture (usually arm64).

GApps are installed immediately after the main system firmware, before the first reboot. In the TWRP menu, you simply add the archive with services to the installation queue along with the firmware or install it in a separate step. Packages vary in size: from minimal (Pico), containing only the store Play, to full versions with all services.

Also at this stage it is often installed Magisk to obtain root accessThis gives full control over the system, allowing you to delete system applications, change fonts and manage energy consumption. However, the presence of root access can become an obstacle to the operation of some protected applications, such as banking clients or streaming ones. services with DRM protection.

⚠️ Attention: The version of the GApps package must strictly correspond to the Android version in the firmware. An attempt to install Android 11 GApps on an Android 12 system will result in an endless reboot (bootloop).

If If you plan to use the phone for gaming or graphics work, it may also be worth flashing compatible GPU drivers if the firmware developer provides them separately. This is mainly true for devices based on chipsets Snapdragonwhere drivers can be updated regardless of the system.

Possible problems and solutions

Even with careful preparation. the process may not go according to plan. The most common problem is when the phone constantly reboots before reaching the desktop. The reason is most often an incompatibility of the GApps version, a damaged firmware file, or a forgotten partition cleaning Bootloopwhen the phone constantly reboots before reaching the desktop. The reason is most often an incompatibility of the GApps version, a damaged firmware file, or a forgotten partition wipe. Data.

To exit the bootloop, you need to boot into TWRP again and try cleaning it. data-i="138">, and then reflash the system again. If this does not help, you should return to the previously saved backup copy (Restore) through the menu Dalvik/Cache, and then reflash the system again. If this does not help, you should return to the previously saved backup copy (Restore) through the menu BackupThat is why creating a backup before any actions is the golden rule of modding.

Another common problem is non-working VoLTE data-i="141"> in 4G/5G networks. This is due to the fact that custom firmware may not contain proprietary modem drivers (RIL) specific to your region or operator. In such cases, flashing the stock modem via Fastboot or searching for special patches on the developer forum sometimes helps.

If the phone does not respond to buttons at all and does not turn on (“soft brick”), try entering the mode Download Mode (for Samsung) or Fastboot and restore the stock firmware using the manufacturer’s official means. This will restore the warranty and functionality, although it will delete all data.

Is it safe to install custom firmware on your main phone?

Using custom firmware as the main system is possible, but requires preparedness for periodic failures. For critical tasks (calls, banking, navigation while traveling), it is safer to use the stock OS or have a spare device.

Will I lose it? the ability to receive security updates?

Depends on the firmware developer. Popular projects (LineageOS, Pixel Experience) release monthly security patches. However, you will depend on enthusiasts, and not on the official schedule of the manufacturer.

Is it possible to return everything back if you don’t like it?

Yes, if you saved the stock recovery image and the official firmware. The return process (unroot and stock return) is usually described in the same topic on the forum where you purchased the custom one.

Does flashing affect battery wear?

High-quality optimized firmware can significantly improve battery life compared to “heavy” stock. However, unstable alpha versions can, on the contrary, cause rapid discharge due to background errors.