JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech III MOBILE APPLICATION DEVELOPMENT Previous Question Paper (August - 2022 - R18)

An Android Virtual Device (AVD) is a configuration that defines the characteristics of an Android phone, tablet, Wear OS, or Android TV device. It acts as an emulator that allows developers to test applications without needing a physical device.

To create an AVD in Android Studio:

1. Open the Device Manager from the Tools menu.
2. Click Create Device.
3. Select a hardware profile (e.g., Pixel 7) and click Next.
4. Select a system image (Android version) and download it if necessary.
5. Verify the configuration, name the AVD, and click Finish.

The Android OS Design is based on a layered architecture:

• Linux Kernel: Provides low-level services like memory management, process management, and hardware drivers.
• Hardware Abstraction Layer (HAL): Provides standard interfaces that expose device hardware capabilities to the higher-level Java API framework.
• Android Runtime (ART): Executes applications and provides core libraries that allow developers to write apps using Java or Kotlin.
• Native C/C++ Libraries: Includes libraries like WebKit, OpenGL, and SQLite that support the functionality of the OS.
• Application Framework: Provides the high-level building blocks used by developers, such as Activity Manager, Content Providers, and View System.
• System Apps: The top layer containing core applications like Dialer, Email, and SMS.

Installing and running applications on Android Studio involves the following steps:

1. Project Setup: Ensure the project is built successfully by clicking Build > Make Project.
2. Device Selection: Select either a configured AVD from the Device Manager or connect a physical device via USB with USB Debugging enabled in Developer Options.
3. Execution: Click the green Run icon (play button) in the top toolbar or press Shift+F10.
4. Deployment: Android Studio compiles the source code into an APK (Android Package), signs it with a debug key, and installs it onto the selected target device.
5. Monitoring: Once installed, the application launches automatically. Use the Logcat window at the bottom of the IDE to monitor system logs, debug output, and runtime errors during execution.