Architecture of Android

In this article, we discuss the Architecture of Android in simple way.

In this article

• What is an architecture?
• Linux.
• Hardware Abstraction Layer(HAL).
• Native Libraries.
• Android Run time.
• Application Framework.
• Applications.

The Android operating system is designed with a layered architecture that ensures flexibility, reliability, and modularity. Its architecture consists of five main layers, each serving a specific purpose. Here’s an overview:

What is an Architecture?

Architecture refers to the overall design, structure, and organization of a system. It defines how different components or layers of the system interact with one another and how they collectively function to achieve the desired outcome.

Types of Android architecture:

The following are the types of Android architecture

1. Linux Kernel

• Foundation of Android:
  The Android OS is built on the Linux Kernel, which acts as a hardware abstraction layer.
• Responsibilities:
  • Device Drivers: Provides drivers for hardware components like display, camera, Wi-Fi, Bluetooth, and more.
  • Process Management: Manages processes and enforces resource allocation.
  • Power Management: Optimizes energy consumption.
  • Security: Enforces security features like SELinux for sandboxing apps.

2. Hardware Abstraction Layer (HAL)

• Definition:
  The HAL serves as an interface between the hardware and higher-level Android services.
• Functionality:
  • Each hardware component (e.g., camera, GPS, sensors) has a HAL module.
  • Ensures that the Android Framework can interact with hardware without needing to know implementation details.

3. Android Runtime (ART)

• Core Role:
  The Android Runtime (ART) provides the runtime environment for Android applications.
• Key Features:
  • Ahead-of-Time (AOT) Compilation: Converts app bytecode into machine code during installation for improved performance.
  • Garbage Collection: Efficiently manages memory to prevent leaks.
  • Dex Files: Executes Dalvik Executable (DEX) files, optimized for minimal memory usage.

4. Native Libraries

• Definition:
  A collection of C/C++ libraries used by Android applications and services.
• Examples of Libraries:
  • Media Libraries: Handle audio, video, and image processing (e.g., libstagefright, OpenMAX).
  • Graphics Libraries: Use OpenGL ES for 2D/3D rendering.
  • SQLite: Provides database support for app data storage.
  • WebKit: Powers the Android WebView for rendering web content.

5. Android Framework

• Definition:
  Provides APIs and core functionality to developers for building applications.
• Key Components:
  • Activity Manager: Manages app lifecycles and activities.
  • Content Providers: Facilitates data sharing between apps.
  • Resource Manager: Accesses resources like layouts, strings, and assets.
  • Notification Manager: Manages notifications sent to the user.
  • View System: Handles the UI elements and layouts.

6. Applications

• Topmost Layer:
  This layer includes the applications installed on the device, such as messaging, email, browser, and user-downloaded apps.
• Built on Framework:
  Apps use the Android Framework APIs to interact with system components and provide functionality to users.

Key Advantages of Android Architecture

1. Modularity: Each layer operates independently, ensuring flexibility and maintainability.
2. Hardware Abstraction: Supports a wide variety of hardware devices without rewriting the OS.
3. Security: Sandboxing and Linux kernel features enhance security.
4. Efficiency: Optimized resource management through ART and native libraries.

The layered design of Android ensures compatibility across devices while maintaining performance, scalability, and security.

Also Read :

• Overview of Android.