diff --git a/app/build.gradle b/app/build.gradle
index 069d6aa..e20c4de 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,14 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 26
-    buildToolsVersion "26.0.1"
+    compileSdkVersion 27
     defaultConfig {
         applicationId "ml.moerail"
         minSdkVersion 15
-        targetSdkVersion 26
+        targetSdkVersion 27
         versionCode 1
-        versionName "2018.03.23"
+        versionName "2018.03.25"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
     buildTypes {
@@ -21,9 +20,9 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
-    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    testCompile 'junit:junit:4.12'
+    testImplementation 'junit:junit:4.12'
 }
diff --git a/app/src/main/java/ml/moerail/MainActivity.java b/app/src/main/java/ml/moerail/MainActivity.java
index c377126..b4db26b 100644
--- a/app/src/main/java/ml/moerail/MainActivity.java
+++ b/app/src/main/java/ml/moerail/MainActivity.java
@@ -20,7 +20,7 @@ protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        webView = (WebView) findViewById(R.id.webView);
+        webView = findViewById(R.id.webView);
         webView.setWebViewClient(new WebViewClient() {
             @Override
             public void onPageFinished(WebView view, String url) {
diff --git a/build.gradle b/build.gradle
index c2eea8e..804e9f4 100644
--- a/build.gradle
+++ b/build.gradle
@@ -3,9 +3,10 @@
 buildscript {
     repositories {
         jcenter()
+        google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.3'
+        classpath 'com.android.tools.build:gradle:3.1.0'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -15,6 +16,7 @@ buildscript {
 allprojects {
     repositories {
         jcenter()
+        google()
     }
 }
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 3710617..b6517bb 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip