How to Create Your First Android App Using Kotlin

If you’ve always wanted to build an Android app but had no idea where to start, this guide is for you. In this beginner-friendly tutorial, we’ll walk you through the process of building your very first Android app using Kotlin, the modern language officially supported by Google for Android development.

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Why Kotlin?

Kotlin is a concise, expressive, and safe programming language that works seamlessly with Java. It has become the preferred language for Android development due to its simplicity and powerful features.

Learn more about Kotlin here:
kotlinlang

What You Need to Get Started

Before you start building, you’ll need to set up your development environment:

1. Install Android Studio

Android Studio is the official IDE (Integrated Development Environment) for Android development. Download it from the official site:
developer.android.com

2. Set Up Your First Project

Once Android Studio is installed, open it and follow these steps:

Click “New Project”
Select “Empty Activity”
Name your app (e.g., “MyFirstApp”)
Choose Kotlin as the language
Click Finish

Android Studio will now create a basic project with the necessary files.

Understanding the Project Structure

Let’s break down some of the important files:

MainActivity.kt – This is your main Kotlin file where you write your logic.
activity_main.xml – This file handles your app’s layout and design.
AndroidManifest.xml – This defines essential information about your app.

Writing Your First Code

Open activity_main.xml and replace the code with:



<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical">

    <TextView
        android:id="@+id/greetingText"
        android:text="Hello, World!"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="24sp"/>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:gravity="center"

android:orientation="vertical">

<TextView

android:id="@+id/greetingText"

android:text="Hello, World!"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:textSize="24sp"/>

</LinearLayout>

Then go to MainActivity.kt and update it with:



package com.example.myfirstapp

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
    }
}

package com.example.myfirstapp

import android.os.Bundle

import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

setContentView(R.layout.activity_main)

}

Running Your App

To run the app:

Click on the green “Run” button in Android Studio.
Choose an emulator or connect a physical device.
Wait for the build to complete and your app will launch!

Congratulations! You’ve just built and launched your first Android app.

Learn More and Practice

To further your skills:

Follow Google’s Android Kotlin guides: https://developer.android.com/kotlin
Try out Kotlin playground for practice: https://play.kotlinlang.org/
Join Kotlin communities: https://kotlinlang.org/community/

Conclusion

Building your first Android app is a major milestone. With tools like Kotlin and Android Studio, you can bring your ideas to life and even publish your apps to the Play Store. Start experimenting, keep learning, and most importantly — have fun coding!