When you pick up a smartphone, tablet, or even a modern smart mirror running a “green robot,” you interact with one of the most complex software ecosystems of our time. Many users mistakenly believe that Android is a completely independent operating system written from scratch by Google engineers, but this is not entirely true. The fundamental answer to the question of what OS Android is based on is Linux kernel, which acts as a link between the device's hardware and its software interface.
It is this kernel that provides the basic functionality necessary for the operation of any computing device: memory management, process scheduling, security and operation with the periphery. However, Google has made such significant changes to the standard kernel, and also created unique add-ons, that Android is often classified as a separate class of mobile operating systems. Understanding this structure is critical for developers, custom ROM enthusiasts, and those who want to deeply understand mobile architecture. Unlike desktop operating systems, where the user often has direct access to system files, in a mobile environment access to the lower layers is strictly limited. This is done for the sake of security and stability, because a failure at the kernel level can lead to complete inoperability mobile architecture.
Unlike desktop operating systems, where the user often has direct access to system files, in a mobile environment access to lower levels is strictly limited. This is done for the sake of safety and stability, because a failure at the kernel level can lead to complete inoperability smartphone. In this article, we will take a detailed look at the layers of architecture, the role of open source code and how exactly Linux has transformed into a platform used by billions of people around the world.
The foundation of the system: the Linux kernel and its modifications
The basis on which the entire Android architecture is built is a modified core Linux. Google chose this base for a reason: Linux is famous for its stability, memory efficiency, and excellent support for a variety of hardware. However, Android cannot be said to use the standard Linux kernel that can be found on servers or desktop computers. Google engineers and the Open Handset Alliance community have made a number of critical changes to adapt the system to the limitations of mobile devices, such as power consumption and touch control.
One of the key differences is the use of specific drivers that are not included in the main branch of Linux development. These drivers allow the operating system to correctly interact with cameras, displays, communication modules and sensors installed by manufacturers smartphones. In addition, the Android kernel implements a mechanism that allows applications to temporarily prevent the system from going into sleep mode to perform background tasks, which is a unique feature of the mobile platform. wakelocks, which allows apps to temporarily prevent the system from going to sleep to perform background tasks, a feature unique to the mobile platform.
⚠️ Attention: When flashing a device or installing a custom kernel Please check compatibility with your specific model. Using a kernel from a different model can lead to irreversible damage to hardware modules, for example, a camera or Wi-Fi module.
It is also worth noting that Google is actively involved in the development of the main Linux kernel, returning many of its developments to the common repository. This allows you to maintain a high level of security and performance. For the average user, this means that their device receives regular security patch updates, even if the visual interface remains the same. Kernel takes all the hard work of allocating processor resources, ensuring a smooth interface even when multitasking.
Why doesn't Android use the stock Linux kernel?
The standard Linux kernel is optimized for desktops and servers where maximum computing performance is a priority. Energy efficiency is becoming a top priority in mobile devices. Google's modifications allow the system to aggressively shut down background processes and manage component power more finely than standard Linux does.
Libraries and Hardware Abstraction Layer (HAL)
Above the Linux kernel is a system libraries layer and a hardware abstraction layer known as HAL (Hardware Abstraction) layer). This layer is a critical bridge that allows upper layers of the operating system to work with hardware without knowing the specifics of each specific chip manufacturer. It is thanks to HAL that application developers can write code that will work on devices from Samsung, Xiaomi, Sony and other brands without the need to rewrite it for each hardware. The libraries included in this layer provide a wide range of functions for working with graphics, sound, databases and web browsing. For example, the library gland.
The libraries included in this layer provide a wide range of functions for working with graphics, sound, databases and web browsing. For example, library Surface Manager controls access to the screen and combining windows of different applications, and SQLite provides work with databases, which is a standard for storing local information on the device. These components are written primarily in C and C++, which guarantees high speed of operations.
The HAL layer also includes specific modules for controlling the camera, Bluetooth, audio and sensors. When you take a photo, the application sends a request through the API, which goes through the framework and into the HAL, and from there into the kernel driver. This layered structure provides flexibility, but also adds latency, which developers are constantly optimizing. Without this layer abstractions creating universal applications for Android would be almost impossible.
If you are a developer and your application behaves strangely on a certain device, the problem often lies not in the application code, but in the HAL implementation by the device manufacturer. Always test software on different models.
Android Runtime (ART)
One of the most significant changes in the Android architecture was the transition from the Dalvik virtual machine to the modern runtime ART (Android Runtime). Starting with Android 5.0 Lollipop, ART became the standard, providing significant performance gains. Unlike its predecessor, which compiled the application code into machine code every time it was launched (JIT compilation), ART uses the Ahead-Of-Time (AOT) compilation method.
This means that when you install an application from the store Google Playit is immediately compiled into machine code that your device's processor can understand. Although the installation process takes a little longer and requires a little more disk space, applications launch instantly and the overall experience becomes smoother. Compilation Coding in advance allows the system to use processor resources more efficiently while using the gadget.
In addition, ART improves memory management and garbage collection, which reduces the number of micro-delays (freezes) during interface operation. For developers, this opens up new optimization opportunities because they can rely on more predictable runtime behavior. It is important to understand that ART is fully compatible with Java bytecode, which allows you to maintain a unified ecosystem of applications.
System applications and user interface
The tip of the Android iceberg is the application level with which the user directly interacts. This includes both pre-installed system applications (calls, SMS, contacts, settings) and third-party software downloaded by the user. They all work in isolated processes, which ensures safety: a failure in one application should not lead to the crash of the entire operating system. The interface that you see - icons, widgets, notification panel - is also part of system applications. Device manufacturers often create their own shells, such as from Samsung, from Xiaomi or from OPPO. These shells completely replace the standard launcher and a set of system utilities, changing the visual style and adding new functions, but (the basic basis) remains the same - it’s still the same Android. operating system.
The interface that you see - icons, widgets, notification panel - is also part of the system applications. Device manufacturers often create their own shells, such as One UI from Samsung, MIUI from Xiaomi or ColorOS from OPPO. These shells completely replace the standard launcher and set of system utilities, changing the visual style and adding new features, but the (basic basis) remains the same - it's still the same Android.
The user can replace many elements of this level: install a different launcher, change the keyboard, use alternative browsers. However, it is impossible to replace system components such as the task manager or file manager at a deep level without rights. This limitation protects the system from inexperienced actions that could violate the integrity of the OS. root impossible. This limitation protects the system from inexperienced actions that could compromise the integrity of the OS.
| Architecture component | Main function | Technology/Language |
|---|---|---|
| Linux kernel | Driver management, memory, security | C, C++ |
| HAL | Hardware abstraction for upper levels | C, C++ |
| Libraries | Graphics, sound, databases, web | C, C++ |
| Android Runtime | Application runtime (ART) | C++, Java |
| Applications | User interface and features | Java, Kotlin |
Open source and AOSP project
The most important characteristic of Android is its openness. The basic version of the operating system is known as AOSP (Android Open Source Project). Any manufacturer can take this code, modify it, and install it on their device without having to pay licensing fees to Google. This was a key factor in the rapid spread of Android around the world, allowing for thousands of smartphone models from hundreds of different brands.
However, it is worth distinguishing between AOSP and Google Services (GMS). While the OS itself is open, apps like the Google Play Store, YouTube, Gmail, and Google Maps are proprietary. To use them legally on a device, the manufacturer must obtain certification from Google. That is why new Huawei smartphones or devices shipped to certain regions may not have a full set of Google services, despite the presence of the operating system itself. Open source has also spawned a huge community of enthusiasts who create custom firmware (LineageOS, Pixel Experience and others). These firmwares allow you to extend the life of older devices, get cleaner Android, or access to the latest features that the manufacturer has no longer released for a particular model. Access to the source code ensures transparency: security experts can analyze the code for vulnerabilities. systems.
Open source has also spawned a huge community of enthusiasts who create custom firmware (LineageOS, Pixel Experience and others). These firmwares allow you to extend the life of older devices, get cleaner Android, or access to the latest features that the manufacturer has no longer released for a particular model. Access to the source code provides transparency: security experts can analyze the code for vulnerabilities.
☑️ Check the device before flashing
Comparison with other mobile OS and the future of the platform
When we talk about what Android is based on, we cannot fail to mention its main competitor - iOS. If Android is based on the Linux kernel, then iOS, in turn, is based on the Darwin (BSD Unix) kernel. This fundamental difference in architecture determines many of the features of file systems, memory management, and security approaches. Linux is more flexible and adaptable for different hardware, while Darwin is optimized for a specific set of Apple devices.
There are other attempts to create alternatives, for example, HarmonyOS from Huawei or KaiOS. HarmonyOS is interesting because in its early versions it actively used AOSP components for compatibility with Android applications, but declares a transition to its own microkernel. This shows that the legacy of Linux and Android has become the de facto standard for the mobile industry, which is difficult for even large players to abandon.
The future of Android involves further integration of artificial intelligence and improved experience with foldable devices. Google continues to develop the project Fuchsia, which is written on the new Zircon core, but there are no plans yet to completely replace Android. Most likely, we will see deep hybridization, where Android applications will run on top of new kernels, preserving the familiar ecosystem for users.
⚠️ Attention: Information about Android version support and the timing of security updates may vary depending on the policy of the device manufacturer. Always check the latest information in the "About Phone" section or on the brand's official website.
Android is not just an application, but a complex multi-layered structure, where Linux provides stability, ART - speed, and open source code - versatility.
Is it possible to completely remove Linux from Android and replace the kernel?
Theoretically this is possible, but in practice it will require rewriting all drivers and system libraries. In fact, it will no longer be Android, but a completely new operating system, even if it can run APK files. Attempts to create Android without a Linux kernel (for example, the Android on Zircon project) are at the experimental stage and are not intended for mass use.
Does the version of the Linux kernel affect the operation of applications?
For most ordinary applications, the kernel version is invisible. However, applications that require deep system access (antiviruses, firewalls, developer tools) may depend on specific kernel functions. Also, newer versions of the kernel better manage the power consumption of modern processors.
Why is Android often called "the poor man's Linux" and is this true?
This is an erroneous and outdated stereotypical opinion. Although Android uses the Linux kernel, its architecture, libraries, and runtime are radically different from classic Linux distributions (like Ubuntu or Debian). Android is optimized to run on devices with limited battery power and touch input, using different process management mechanisms.
How to find the kernel version on your device?
You can find this information by going to Settings → About phone → Software information (the path may vary depending on the model). There will be a line "Kernel version" containing the Linux version number and build date.