Your First Android App: A Step-by-Step Guide to Using Android Studio (2025)
Your First Android App: A Step-by-Step Guide to Android Studio (2025)

Your First Android App: A Step-by-Step Guide to Android Studio (2025)

Ever had an idea for a mobile app but had no idea where to start? The world of app development can seem intimidating, but with today's powerful and user-friendly tools, creating a basic application is more accessible than ever. This guide will walk you through every step of the process, from installing the necessary software to creating and running your very first "Hello, Android!" app using Android Studio, the official tool for building Android applications.

The Modern Toolkit: Kotlin and Jetpack Compose

For this 2025 guide, we will be using the modern, industry-standard toolset recommended by Google:

  • Kotlin: The official programming language for Android development. It's a modern, powerful, and concise language that has largely replaced Java for new app development.
  • Jetpack Compose: The modern UI toolkit for building native Android interfaces. Instead of complex XML layouts, Compose allows you to build your app's UI by writing simple, descriptive Kotlin functions.

Step 1: Installing Android Studio

Your journey begins with installing the Integrated Development Environment (IDE), which is the software that brings all the development tools together.

  1. Go to the official Android Developer website and download the latest version of Android Studio.
  2. Run the installer and follow the on-screen instructions of the setup wizard. Accept the default settings, which will install Android Studio, the Android SDK (Software Development Kit), and other essential components.
  3. The first launch might take some time as it downloads and sets up the latest SDKs.

Step 2: Creating Your First Project

Once Android Studio is running, it's time to create the project for your app.

  1. On the welcome screen, click on "New Project."
  2. In the "Templates" window, select "Phone and Tablet," and then choose the "Empty Activity" template. Click "Next."
  3. On the configuration screen, you'll need to set a few things:
    • Name: Give your application a name, like "MyFirstApp".
    • Package name: This is a unique identifier for your app on the Play Store. It's conventionally written in reverse domain name format (e.g., `com.yourname.myfirstapp`).
    • Language: Ensure this is set to Kotlin.
    • Minimum SDK: This determines the oldest version of Android your app will run on. The default is usually fine.
  4. Click "Finish." Android Studio will now build your project, which may take a few minutes.

Step 3: Writing Your First Line of Code

Android Studio will open with your new project. On the left, in the Project window, navigate to `app > java > com.yourname.myfirstapp` and double-click on the `MainActivity.kt` file to open it.

This is the main entry point of your app. You'll see some boilerplate code. Find the `setContent` block inside the `onCreate` function. This is where you define your app's UI. Delete the default content inside `setContent` and replace it with this single line:

setContent {
    Text(text = "Hello, Android!")
}

Android Studio might ask you to import the `Text` component. If it does, simply click on the red `Text` word and press Alt+Enter (or Option+Enter on Mac) and select "Import."

Step 4: Running Your App on an Emulator

Now for the exciting part: seeing your app run. We'll use an emulator, which is a virtual phone running on your computer.

  1. In the top toolbar of Android Studio, you'll see a dropdown menu that says "". Click on it and select "Device Manager."
  2. In the Device Manager window, click "Create Device." Select a phone model (like a Pixel) and click "Next."
  3. Select a recommended system image (the Android OS version) and click "Next." Give your virtual device a name and click "Finish."
  4. Close the Device Manager. Your new virtual device should now be selected in the top toolbar.
  5. Click the green "Run" button (a triangle icon) in the toolbar.

Android Studio will build your app, launch the emulator, and after a minute, you should see your app appear on the virtual phone screen with the text "Hello, Android!"

Conclusion: The Journey Begins

Congratulations! You have successfully created your very first Android application. You've installed the professional tools, written a line of code, and run a working app on an emulator. While this is a simple start, you have now built the foundation from which all other Android development skills will grow. The journey to building the next great app starts with exactly these steps.