What is Android and how does it work

Android is an open-source, Linux-based mobile operating system developed by Google. It is designed primarily for touchscreen devices like smartphones and tablets

Architecture

• Android uses a layered architecture consisting of:
  • Linux kernel at the bottom
  • Hardware Abstraction Layer (HAL)
  • Native C/C++ libraries
  • Android Runtime (ART)
  • Java API Framework
  • System Apps at the top layer

Core components

• Linux kernel: Provides low-level functionality like memory management, process management, networking, etc.
• Android Runtime (ART): Executes Android apps, replacing the older Dalvik VM
• Native libraries: Written in C/C++, provide core functionality
• Java API Framework: APIs for developers to build apps

Key features

• Open source: Allows developers to freely access and modify source code
• Customizable: Users can customize themes, widgets, apps
• Google services integration
• Multitasking capabilities
• Regular updates with new features
• Large app ecosystem via Google Play Store

How it works

• Apps run in their own processes with their own instances of ART
• Uses ahead-of-time (AOT) and just-in-time (JIT) compilation
• Manages memory and processes automatically to optimize battery life
• Provides APIs for developers to access device hardware and features
• Uses the Android application framework to handle app lifecycles

Development

• Apps are typically written in Java or Kotlin
• Uses APK files for app packaging and distribution
• Provides extensive development tools and resources for app creators