How to retrieve shared preferences of other application in Android?

This example demonstrates how to do I in android.

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"?>
<LinearLayout
xmlns:android="https://schemas.android.com/apk/res/android"
   xmlns:tools="https://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical"
   android:padding="16dp"
   tools:context=".MainActivity">
   <EditText
      android:id="@+id/etEmail"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_marginTop="20dp"
      android:ems="10"
      android:hint="Email"
      android:inputType="textEmailAddress" />
   <EditText
      android:id="@+id/etName"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:ems="10"
      android:hint="Name"
      android:inputType="text" />
   <Button
      android:layout_marginTop="50dp"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:onClick="Save"
      android:text="Save" />
   <Button
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:onClick="Clear"
      android:text="Clear Data" />
   <Button
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:onClick="Retrieve"
      android:text="Retrieve Data" />
</LinearLayout>

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

import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
   EditText etName, etEmail;
   SharedPreferences sharedPreferences;
   public static final String myPreference = "myPref";
   public static final String Name = "nameKey";
   public static final String Email = "emailKey";
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      etName = findViewById(R.id.etName);
      etEmail = findViewById(R.id.etEmail);
      sharedPreferences = getSharedPreferences(myPreference, Context.MODE_PRIVATE);
      if (sharedPreferences.contains(Name)) {
         etName.setText(sharedPreferences.getString(Name, ""));
      }
      if (sharedPreferences.contains(Email)) {
         etEmail.setText(sharedPreferences.getString(Email, ""));
      }
   }
   public void Clear(View view) {
      etName = findViewById(R.id.etName);
      etEmail = findViewById(R.id.etEmail);
      etName.setText("");
      etEmail.setText("");
      Toast.makeText(MainActivity.this, "Cleared", Toast.LENGTH_LONG).show();
   }
   public void Retrieve(View view) {
      etName = findViewById(R.id.etName);
      etEmail = findViewById(R.id.etEmail);
      sharedPreferences = getSharedPreferences(myPreference, Context.MODE_PRIVATE);
      if (sharedPreferences.contains(Name)) {
         etName.setText(sharedPreferences.getString(Name, ""));
      }
      if (sharedPreferences.contains(Email)) {
         etEmail.setText(sharedPreferences.getString(Email, ""));
      }
      Toast.makeText(MainActivity.this, "Retrieved", Toast.LENGTH_LONG).show();
   }
   public void Save(View view) {
      String name = etName.getText().toString();
      String email = etEmail.getText().toString();
      SharedPreferences.Editor editor = sharedPreferences.edit();
      editor.putString(Name, name);
      editor.putString(Email, email);
      editor.apply();
      Toast.makeText(MainActivity.this, "Saved", Toast.LENGTH_LONG).show();
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="https://schemas.android.com/apk/res/android" package="app.com.sample">
   <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 the android studio, open one of your project's activity files and click Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −