Extracting applications from Android firmware

Many Android users are faced with a situation where they need to obtain the installation file of a specific application directly from the device’s system image. This may be required to create your own custom firmware, transfer specific system software to another device, or save a working version of the app before updating the system. Understanding how to extract applications from Android firmwareopens up wide opportunities for modding and deep customization of the gadget.

Standard installation methods via Google Play are not always suitable, since many system utilities are distributed only as part of the factory firmware image. The extraction process ranges from simple actions with superuser rights to complex manipulation of the system image via a computer. In the article we will analyze all the current methods, from using special utilities to manual copying via ADB.

It is important to understand that working with system files requires caution. Accidental removal or modification of critical components may result in unstable operation Android. However, if your goal is to copy (extract) files, the risk is minimal if you follow basic security rules. We will look at methods that are suitable for both ordinary users and advanced enthusiasts.

Device preparation and necessary tools

Before starting any manipulations with the file system, you must ensure access to protected memory sections. In most cases, complete extraction of system applications requires root access. Without them, access to the directory /system/app or /system/priv-app will be closed for reading and copying. If your device is already rooted, you can skip this step.

If there is no root access, the only legal way is to use USB debugging and the ADB (Android Debug Bridge) tool. To do this, you need to activate developer mode in your phone settings. Go to Settings → About phone and quickly click 7 times on the item Build number. After the message “You have become a developer” appears, return to the main settings menu and find the new section For developers.

⚠️ Attention: Activating USB debugging makes the device visible to computer. Do not connect your phone to unknown PCs in public places to avoid unauthorized access to your data.

You will also need a computer with ADB and Fastboot drivers installed. An alternative is to use file managers that support root access directly on the smartphone, such as Root Explorer or Solid Explorer. The choice of tool depends on how deeply you plan to penetrate into the firmware structure.

Using specialized APK extractors

The easiest and safest way to get the application installation file is to use specialized software. There are many extractor apps that can find APK files in system partitions and save them into user-accessible memory. This method is ideal if you need to quickly save one or more applications without deep analysis of the firmware structure.

Popular utilities such as APK Extractor or App Backup & Restorescan installed packages and offer to save them in .apkformat. Some applications require root access to work with system software, while others can only extract user apps. When choosing a tool, pay attention to support split APKs (Split APKs), since modern applications often consist of several parts.

The process usually looks like this: you launch the extractor, find the desired application in the list (for example, a system camera or launcher) and click the "Extract" button or "Export". The file is saved in a folder Download or a special directory of the app, from where it can be transferred to another device or sent by mail. This is the most friendly method for beginners.

Manual extraction through a file manager with Root access

For those who prefer complete control over the process, the manual copying method through an advanced file manager is suitable. This method allows you not only to copy a file, but also to study the structure of application placement in the firmware. You will need an application with superuser rights that can mount the system partition in read/write or at least read mode.

System applications in Android are stored in several key directories. Basic paths you need to know:

• 📂 /system/app — here are regular system applications that can be deleted without critical consequences for the system.
• 📂 /system/priv-app —this folder contains privileged applications with extended access to OS functions (for example, phone book, settings, Google services).
• 📂 /data/app —directory for custom applications installed from the store or third-party sources.

To extract the application, go to one of the system folders, find the directory with the name of the desired package (for example, com.android.camera) and copy the file .apk to the internal memory or SD card. Please note that in modern versions of Android, the folder structure may be more complicated, and the APK file may be located inside subfolders with unclear names containing hashes or versions.

⚠️ Warning: Never try to delete or move files directly from folders /system or /priv-app without creating a complete backup. The error may cause the phone to stop booting (bootloop).

Why are some folders empty?

New versions of Android (starting from 10 and higher) use the mechanism of dynamic partitions and Project Treble. Some system applications can be mounted from the vendor or product image, so in the standard file manager you can only see shortcuts or empty directories. To access real files, you may need to unmount images or use specific ADB commands.

Extracting applications via ADB from a computer

The method of use Android Debug Bridge is the most universal and does not always require root access if you just need to copy a file that has read access. This method is preferable for advanced users, as it allows you to automate the process and work with devices on which it is difficult to gain full access to the file system through the GUI.

First, make sure that USB debugging is enabled and the computer can see the device. Open a command line or terminal on your PC and enter the command to enter the device shell:

adb shell

Once you have access to the shell, you can use the command pm list packages to find the exact package name of the desired application. Knowing the name of the package, you can find the path to its file using the command pm path com.example.app. The system will return the full path to the APK file.

Next, use the command pull to download the file to your computer:

adb pull /path/to/file.apk C:/Extracted_Apps/

This method ensures that you copy exactly the file you want which is currently active in the system. It is also convenient for mass extraction of applications using scripts, which is useful when preparing custom firmware.

ADB command	Description of action	Required rights
adb devices	Checking device connection	No
adb shell pm list packages	List all installed packages	No
adb shell pm path <package_name>	Get the full path to the APK file	No
adb pull <source> <dest>	Copy a file from the phone to the PC	Depends on the file

Analyzing and unpacking the firmware image on a PC

If you have a full firmware file (for example system.img), but do not have the device itself at hand, you can extract applications directly from the image. This method is complex and requires knowledge of the Android file systems format (usually ext4 or erofs). You will need special utilities to mount or unpack images, such as Android Image Kitchen or Ext4Unpacker.

The process begins by unpacking the firmware archive (often a ZIP or TAR) to gain access to the binary images of the partitions. Then system.img is processed by the unpack tool, which converts it into a regular folder with a file structure. After that, you can go to the resulting directory, find the folder app or priv-app and copy the necessary APK files in the usual way through Windows or Linux Explorer.

This approach is indispensable for developers of custom recovery and firmware, as it allows you to modify the composition of the system software before installing it on the device. However, for the average user who just wants to save one application, this method is redundant and time-consuming. In addition, it is worth considering that images can be encrypted or compressed with manufacturer-specific algorithms.

⚠️ Attention: The structure of firmware from different manufacturers (Samsung, Xiaomi, Pixel) is very different. The decompression tools must match the type of image compression and formatting. Using the wrong utility can damage the image data.

Features of working with split applications (Split APKs)

In modern versions of Android, Google has implemented format Android App Bundlewhich led to the appearance of split APKs. This means that the application is no longer a single file, but consists of a base APK and several configuration files (for a specific screen resolution, processor architecture, language).

If you try to extract such an application using the old methods, you will only get a base file that will not install on another device. For correct extraction, you must use tools that support the format .apks or can collect splits into one file. Utilities like Sai (Split APKs Installer) or advanced functions ADB allow you to export all parts of the application.

If you plan to transfer an extracted application, make sure you build the complete package. Otherwise, the user will receive an "App not installed" installation error. This is a critically important nuance when working with popular instant messengers and heavy games, which almost always use resource sharing.

Is it possible to extract an application without root access?

Yes, this is possible. You can use the ADB command adb shell pm path to find the path and adb pull to copy if the file is readable. Also, many APK extractors work without root, but only for user applications, not system ones.

Where is application data stored after extracting the APK?

The APK file contains only installation code and resources. User data (logins, settings, saves) is stored in the /data/datasection. To save them, you need to make a full backup (for example, through Titanium Backup); simply copying the APK will not save your data.

Is it safe to install extracted system applications on another phone?

Not always. System applications often depend on specific libraries and frameworks for a particular model or version of Android. Installing a system launcher or settings from one phone to another may cause conflicts, crashes or non-functional functions.

What to do if the extracted APK does not install?

Check the Android version: the application may require a newer or older version of the OS. Make sure you have extracted all parts of the Split APK. It is also possible that the application is signed with a system key and cannot be installed as a regular user application without re-signing.

How to find the exact package name of the application?

Use the ADB command pm list packages | grep "part_of_name" or install an application on your phone like "App Inspector" that displays the technical name of the package (for example, com.android.chrome) for any installed app.