Android App

Building blocks of the Android ecosystem

App Structure

An Android app is a package (APK) containing code, resources, and a manifest. It consists of components that interact with the system and users.

Core Components

Activities

UI screens for user interaction and navigation between different parts of the app.

Services

Background tasks without UI that can run independently of activities.

Broadcast Receivers

Respond to system-wide events and notifications from other apps.

Content Providers

Manage shared app data and provide data access to other applications.

App Lifecycle

Android manages app components' lifecycles, ensuring efficient resource use and smooth user experience. Developers must handle state transitions and resource cleanup.

Created
Started
Resumed
Running
Paused
Stopped
Destroyed

Interaction with OS

  • Apps communicate with the OS via the Framework and system services.
  • Permissions control access to sensitive features and device resources.
  • Apps can interact with each other using Intents and Content Providers.
  • Background processing is managed through Services and WorkManager.

Learn More

Explore the official Android app development documentation for comprehensive guides.

Android App Fundamentals