diff --git a/.gitignore b/.gitignore
old mode 100644
new mode 100755
diff --git a/LICENSE b/LICENSE
old mode 100644
new mode 100755
diff --git a/README.md b/README.md
old mode 100644
new mode 100755
diff --git a/app/build.gradle b/app/build.gradle
old mode 100644
new mode 100755
index e505fcf..976be5d
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -7,13 +7,13 @@ android {
         exclude 'META-INF/NOTICE'
     }
 
-    compileSdkVersion 21
-    buildToolsVersion "21.1.1"
+    compileSdkVersion 25
+    buildToolsVersion '25.0.0'
 
     defaultConfig {
         applicationId "com.firebase.androidchat"
-        minSdkVersion 10
-        targetSdkVersion 21
+        minSdkVersion 19
+        targetSdkVersion 25
         versionCode 1
         versionName "1.0"
     }
@@ -27,5 +27,5 @@ android {
 
 dependencies {
     compile fileTree(dir: 'libs', include: ['*.jar'])
-    compile 'com.firebase:firebase-client-android:2.0.3+'
+    compile 'com.firebase:firebase-client-android:2.5.2'
 }
diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
old mode 100644
new mode 100755
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/java/com/firebase/androidchat/Chat.java b/app/src/main/java/com/firebase/androidchat/Chat.java
old mode 100644
new mode 100755
diff --git a/app/src/main/java/com/firebase/androidchat/ChatApplication.java b/app/src/main/java/com/firebase/androidchat/ChatApplication.java
old mode 100644
new mode 100755
diff --git a/app/src/main/java/com/firebase/androidchat/ChatListAdapter.java b/app/src/main/java/com/firebase/androidchat/ChatListAdapter.java
old mode 100644
new mode 100755
diff --git a/app/src/main/java/com/firebase/androidchat/FirebaseListAdapter.java b/app/src/main/java/com/firebase/androidchat/FirebaseListAdapter.java
old mode 100644
new mode 100755
diff --git a/app/src/main/java/com/firebase/androidchat/MainActivity.java b/app/src/main/java/com/firebase/androidchat/MainActivity.java
old mode 100644
new mode 100755
diff --git a/app/src/main/res/drawable/firebase_logo.png b/app/src/main/res/drawable/firebase_logo.png
old mode 100644
new mode 100755
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/layout/chat_message.xml b/app/src/main/res/layout/chat_message.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/values-sw720dp-land/dimens.xml b/app/src/main/res/values-sw720dp-land/dimens.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
old mode 100644
new mode 100755
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
old mode 100644
new mode 100755
diff --git a/build.gradle b/build.gradle
old mode 100644
new mode 100755
index e26cdee..404c880
--- a/build.gradle
+++ b/build.gradle
@@ -4,7 +4,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:1.0.0'
+        classpath 'com.android.tools.build:gradle:3.0.0-beta2'
     }
 }
 
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
old mode 100644
new mode 100755
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
old mode 100644
new mode 100755
index 8b1883b..9894281
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Fri Dec 05 16:24:11 PST 2014
+#Sun Aug 13 00:09:45 JST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.1-rc-1-all.zip
diff --git a/gradlew.bat b/gradlew.bat
old mode 100644
new mode 100755
diff --git a/screenshot.png b/screenshot.png
old mode 100644
new mode 100755
diff --git a/settings.gradle b/settings.gradle
old mode 100644
new mode 100755