How to get the device's IMEI/ESN programmatically in android using Kotlin?

This example demonstrates how to get the device's IMEI/ESN programmatically in android using Kotlin.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context=".MainActivity">
   <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerHorizontal="true"
      android:layout_marginTop="50dp"
      android:text="Tutorials Point"
      android:textAlignment="center"
      android:textColor="@android:color/holo_green_dark"
      android:textSize="32sp"
      android:textStyle="bold" />
   <Button
      android:id="@+id/button"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_above="@id/textView"
      android:layout_centerInParent="true"
      android:layout_marginBottom="20sp"
      android:text="Check IEMI number" />
   <TextView
      android:id="@+id/textView"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:hint="Your IEMI number"
      android:textColor="@android:color/background_dark"
      android:textSize="16sp" />
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.kt

import android.Manifest
import android.content.Context
import android.content.pm.PackageManager
import android.os.Bundle
import android.telephony.TelephonyManager
import android.widget.Button
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
class MainActivity : AppCompatActivity() {
   lateinit var button: Button
   lateinit var textView: TextView
   private lateinit var IMEINumber: String
   private val REQUEST_CODE = 101
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
      textView = findViewById(R.id.textView)
      button = findViewById(R.id.button)
      button.setOnClickListener {
         val telephonyManager = getSystemService(Context.TELEPHONY_SERVICE) as
         TelephonyManager
         if (ActivityCompat.checkSelfPermission(this@MainActivity,
         Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this@MainActivity,
            arrayOf(Manifest.permission.READ_PHONE_STATE), REQUEST_CODE)
            return@setOnClickListener
         }  
         IMEINumber = telephonyManager.deviceId
         textView.text = IMEINumber
      }
   }
   override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String?>,
   grantResults: IntArray) {
      when (requestCode) {
         REQUEST_CODE -> {
            if (grantResults.isNotEmpty() && grantResults[0] ==
            PackageManager.PERMISSION_GRANTED) {
               Toast.makeText(this, "Permission granted.", Toast.LENGTH_SHORT).show()
            } else {
               Toast.makeText(this, "Permission denied.", Toast.LENGTH_SHORT).show()
            }
         }
      }
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.q11">
   <uses-permission android:name="android.permission.READ_PHONE_STATE" />
   <uses-permission android:name="android.permission.READ_PRIVILEGED_PHONE_STATE" />
   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click the Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen