diff --git a/.idea/misc.xml b/.idea/misc.xml
index ac8866a..4443ac2 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -9,6 +9,14 @@
         <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_gps.xml" value="0.13095238095238096" />
         <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_login.xml" value="0.13221884498480244" />
         <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_main.xml" value="0.25" />
+        <entry key="..\:/Users/student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_change_pw.xml" value="0.22" />
+        <entry key="..\:/Users/student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_login.xml" value="0.5" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/drawable-v24/ic_launcher_foreground.xml" value="0.1425" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/drawable/ic_baseline_my_location_24.xml" value="0.1" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/drawable/ic_launcher_background.xml" value="0.1425" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_gps.xml" value="0.13095238095238096" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_login.xml" value="0.13221884498480244" />
+        <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_main.xml" value="0.25" />
         <entry key="..\:/Users/Student/StudioProjects/NemophilaClient/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml" value="0.226" />
         <entry key="..\:/Users/student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_main.xml" value="0.228125" />
         <entry key="..\:/Users/student/StudioProjects/NemophilaClient/app/src/main/res/layout/activity_maps.xml" value="0.17074275362318841" />
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c421826..fd8224c 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -50,11 +50,10 @@
             android:name=".LoginActivity"
             android:exported="true"
             android:label="@string/title_activity_login">
-<!--             <intent-filter>-->
-<!--             <action android:name="android.intent.action.MAIN" />-->
-
-<!--             <category android:name="android.intent.category.LAUNCHER" />-->
-<!--             </intent-filter>-->
+        </activity>
+        <activity android:name=".ChangePwActivity">
+            android:name=".ChangePwActivity"
+            android:exported="true"
         </activity>
         <activity
             android:name=".RequestedActivity"
@@ -84,11 +83,11 @@
             android:name=".MainActivity"
             android:exported="true"
             android:label="@string/title_activity_maps">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
+<!--            <intent-filter>-->
+<!--                <action android:name="android.intent.action.MAIN" />-->
 
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
+<!--                <category android:name="android.intent.category.LAUNCHER" />-->
+<!--            </intent-filter>-->
         </activity>
 
         <activity
diff --git a/app/src/main/java/com/example/nemophila/ChangePwActivity.java b/app/src/main/java/com/example/nemophila/ChangePwActivity.java
new file mode 100644
index 0000000..6dea40f
--- /dev/null
+++ b/app/src/main/java/com/example/nemophila/ChangePwActivity.java
@@ -0,0 +1,75 @@
+package com.example.nemophila;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.view.View;
+import android.widget.EditText;
+
+import com.example.nemophila.entities.Account;
+import com.example.nemophila.resources.AccountsRest;
+
+import retrofit2.Call;
+import retrofit2.Callback;
+import retrofit2.Response;
+import retrofit2.Retrofit;
+import retrofit2.converter.jackson.JacksonConverterFactory;
+
+public class ChangePwActivity extends AppCompatActivity {
+
+    private Retrofit retrofit;
+    private AccountsRest AccountsRest;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_change_pw);
+        //通信の初期化
+        this.retrofit = new Retrofit.Builder()
+                .baseUrl("http://nitta-lab-www.is.konan-u.ac.jp/nemophila/")
+                .addConverterFactory(JacksonConverterFactory.create())
+                .build();
+        this.AccountsRest = retrofit.create(AccountsRest.class);
+
+
+        findViewById(R.id.ChangePassword).setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                EditText edituid = (EditText) findViewById(R.id.editTextUserid);
+                String uid = edituid.getText().toString();
+                EditText editoldtpw = (EditText) findViewById(R.id.editTextTextOldPassword);
+                String oldPw = editoldtpw.getText().toString();
+                EditText editnewpw = (EditText) findViewById(R.id.editTextTextNewPassword);
+                String newPw = editnewpw.getText().toString();
+                Nemophila nemophila =  new Nemophila();
+                String token = nemophila.getToken();
+
+                // 通信
+                Call<Void> call = AccountsRest.changePw(uid,oldPw,newPw,token);
+
+                call.enqueue(new Callback<Void>() {
+                    @Override
+                    public void onResponse(Call<Void> call, Response<Void> response) {
+                        if (response.isSuccessful()) {
+                            System.out.println("通信成功:changeBelongsAndMaster");
+                            Intent intent = new Intent(ChangePwActivity.this, LoginActivity.class);
+                            startActivity(intent);
+                        } else {
+                            System.out.println("通信可能：changeBelongsAndMaster: " + response.code());
+//                            if (response.code() == 500){
+//                                ((TextView) findViewById(R.id.textView)).setText("The UserName you gave is already in use.");
+//                            }else if (response.code() == 404){
+//                                ((TextView) findViewById(R.id.textView)).setText("SignUp failed. Please enter the correct credentials.");
+//                            }
+                        }
+                    }
+                    @Override
+                    public void onFailure(Call<Void> call, Throwable t) {
+                        System.out.println("通信失敗:changeBelongsAndMaster");
+                    }
+                });
+            }
+        });
+    }
+}
diff --git a/app/src/main/java/com/example/nemophila/LoginActivity.java b/app/src/main/java/com/example/nemophila/LoginActivity.java
index bf945c6..f8310d6 100644
--- a/app/src/main/java/com/example/nemophila/LoginActivity.java
+++ b/app/src/main/java/com/example/nemophila/LoginActivity.java
@@ -6,11 +6,11 @@
 import android.os.Bundle;
 import android.view.View;
 import android.widget.EditText;
+import android.widget.TextView;
 
+import com.example.nemophila.entities.Account;
 import com.example.nemophila.resources.AccountsRest;
 
-import java.util.HashMap;
-
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
@@ -43,22 +43,27 @@
                 String pw = editpw.getText().toString();
 
                 // 通信
-                Call<HashMap> call = AccountsRest.getAccounts();
+                Call<Account> call = AccountsRest.getAccounts(uid,pw);
 
-                call.enqueue (new Callback<HashMap>() {
+                call.enqueue (new Callback<Account>() {
                     @Override
-                    public void onResponse(Call<HashMap> call, Response<HashMap> response) {
+                    public void onResponse(Call<Account> call, Response<Account> response) {
                         if (response.isSuccessful()) {
                             System.out.println("通信成功:changeBelongsAndMaster");
                             Intent intent = new Intent(LoginActivity.this,MainActivity.class);
                             startActivity(intent);
                         } else {
                             System.out.println("通信可能：changeBelongsAndMaster: " + response.code());
+                                if (response.code() == 500){
+                                    ((TextView) findViewById(R.id.textView)).setText("Invalid UserID or Password");
+                                }else if (response.code() == 404){
+                                    ((TextView) findViewById(R.id.textView)).setText("Login failed. Please enter the correct credentials.");
+                                }
                         }
                     }
 
                     @Override
-                    public void onFailure(Call<HashMap> call, Throwable t) {
+                    public void onFailure(Call<Account> call, Throwable t) {
                         System.out.println("通信失敗:changeBelongsAndMaster");
                     }
                 });
@@ -71,5 +76,12 @@
                 startActivity(intent);
             }
         });
+        findViewById(R.id.ForgotPW).setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                Intent intent = new Intent(LoginActivity.this, ChangePwActivity.class);
+                startActivity(intent);
+            }
+        });
     }
 }
diff --git a/app/src/main/java/com/example/nemophila/SignUpActivity.java b/app/src/main/java/com/example/nemophila/SignUpActivity.java
index cc01b38..bccc61a 100644
--- a/app/src/main/java/com/example/nemophila/SignUpActivity.java
+++ b/app/src/main/java/com/example/nemophila/SignUpActivity.java
@@ -2,15 +2,15 @@
 
 import androidx.appcompat.app.AppCompatActivity;
 
+import android.content.Intent;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.EditText;
+import android.widget.TextView;
 
 import com.example.nemophila.entities.Account;
 import com.example.nemophila.resources.AccountsRest;
 
-import java.util.HashMap;
-
 import retrofit2.Call;
 import retrofit2.Callback;
 import retrofit2.Response;
@@ -50,8 +50,15 @@
                     public void onResponse(Call<Account> call, Response<Account> response) {
                         if (response.isSuccessful()) {
                             System.out.println("通信成功:changeBelongsAndMaster");
+                            Intent intent = new Intent(SignUpActivity.this,MainActivity.class);
+                            startActivity(intent);
                         } else {
                             System.out.println("通信可能：changeBelongsAndMaster: " + response.code());
+                            if (response.code() == 500){
+                                ((TextView) findViewById(R.id.textView)).setText("The UserName you gave is already in use.");
+                            }else if (response.code() == 404){
+                                ((TextView) findViewById(R.id.textView)).setText("SignUp failed. Please enter the correct credentials.");
+                            }
                         }
                     }
 
diff --git a/app/src/main/res/layout/activity_change_pw.xml b/app/src/main/res/layout/activity_change_pw.xml
new file mode 100644
index 0000000..761857f
--- /dev/null
+++ b/app/src/main/res/layout/activity_change_pw.xml
@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".ChangePwActivity">
+
+    <EditText
+        android:id="@+id/editTextUserid"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="172dp"
+        android:ems="10"
+        android:hint="UserID"
+        android:inputType="textPersonName"
+        android:minHeight="48dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.502"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <EditText
+        android:id="@+id/editTextTextOldPassword"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:ems="10"
+        android:hint="OldPassword"
+        android:inputType="textPassword"
+        android:minHeight="48dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/editTextUserid" />
+
+    <EditText
+        android:id="@+id/editTextTextNewPassword"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:hint="NewPassword"
+        android:inputType="textPassword"
+        android:minHeight="48dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/editTextTextOldPassword" />
+
+    <Button
+        android:id="@+id/ChangePassword"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="76dp"
+        android:text="ChangePassword"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.498"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/editTextTextNewPassword" />
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_login.xml b/app/src/main/res/layout/activity_login.xml
index d12efd2..79e37dc 100644
--- a/app/src/main/res/layout/activity_login.xml
+++ b/app/src/main/res/layout/activity_login.xml
@@ -10,22 +10,25 @@
         android:id="@+id/LoginButton"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="Login"
+        android:text="@string/login"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintHorizontal_bias="0.5"
+        app:layout_constraintHorizontal_bias="0.498"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/editTextTextNewPassword" />
+        app:layout_constraintTop_toBottomOf="@+id/editTextTextNewPassword"
+        app:layout_constraintVertical_bias="0.2" />
 
     <EditText
         android:id="@+id/editTextUserID"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="188dp"
+        android:autofillHints=""
         android:ems="10"
+        android:hint="@string/userid"
         android:inputType="textPersonName"
         android:minHeight="48dp"
-        android:text="UserID"
+        android:textColorHint="#757575"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
@@ -34,10 +37,12 @@
         android:id="@+id/editTextTextNewPassword"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:autofillHints=""
         android:ems="10"
-        android:hint="@string/title_activity_login"
+        android:hint="@string/password"
         android:inputType="textPassword"
         android:minHeight="48dp"
+        android:textColorHint="#757575"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintHorizontal_bias="0.5"
         app:layout_constraintStart_toStartOf="parent"
@@ -47,10 +52,29 @@
         android:id="@+id/SignUp"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginTop="56dp"
-        android:text="SignUp"
+        android:text="@string/signup"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintHorizontal_bias="0.498"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@+id/LoginButton" />
+
+    <TextView
+        android:id="@+id/textView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="28dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.498"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/editTextTextNewPassword" />
+
+    <Button
+        android:id="@+id/ForgotPW"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="@string/forgot_password"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.497"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/SignUp" />
 </androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_sign_up.xml b/app/src/main/res/layout/activity_sign_up.xml
index 8069609..ff65596 100644
--- a/app/src/main/res/layout/activity_sign_up.xml
+++ b/app/src/main/res/layout/activity_sign_up.xml
@@ -11,10 +11,12 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="204dp"
+        android:autofillHints=""
         android:ems="10"
+        android:hint="@string/username"
         android:inputType="textPersonName"
         android:minHeight="48dp"
-        android:text="Name"
+        android:textColorHint="#757575"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintHorizontal_bias="0.502"
         app:layout_constraintStart_toStartOf="parent"
@@ -25,10 +27,12 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="2dp"
+        android:autofillHints=""
         android:ems="10"
-        android:hint="@string/title_activity_sign_up"
+        android:hint="@string/password"
         android:inputType="textPassword"
         android:minHeight="48dp"
+        android:textColorHint="#757575"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@+id/editTextTextUserName" />
@@ -38,7 +42,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="144dp"
-        android:text="Make a new Account"
+        android:text="@string/make_a_new_account"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintHorizontal_bias="0.498"
         app:layout_constraintStart_toStartOf="parent"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index d650b72..02aafa7 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -8,5 +8,13 @@
     <string name="title_activity_sign_up">SignUpActivity</string>
     <string name="title_activity_test">TestActivity</string>
     <string name="title_activity_gps">GpsActivity</string>
+    <string name="username">UserName</string>
+    <string name="make_a_new_account">Make a new Account</string>
+    <string name="password">Password</string>
+    <string name="login">Login</string>
+    <string name="Password">password</string>
+    <string name="signup">SignUp</string>
+    <string name="userid">UserID</string>
+    <string name="forgot_password">Forgot Password?</string>
 
 </resources>
\ No newline at end of file