diff --git a/.travis.yml b/.travis.yml
index 12f87c50..299468db 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -27,6 +27,7 @@ android:
     components:
         - tools
         - build-tools-27.0.0
+        - build-tools-26.0.2
         - extra-android-m2repository
         - extra-google-m2repository
 
diff --git a/build.gradle b/build.gradle
index ff713c26..338af4a1 100644
--- a/build.gradle
+++ b/build.gradle
@@ -17,6 +17,7 @@ buildscript {
         google()
         jcenter()
     }
+
     dependencies {
         classpath 'com.android.tools.build:gradle:3.0.1'
         classpath 'com.google.gms:google-services:3.1.1'
diff --git a/mobile/build.gradle b/mobile/build.gradle
index 48e42a1e..e9fee92c 100644
--- a/mobile/build.gradle
+++ b/mobile/build.gradle
@@ -32,8 +32,8 @@ android {
         applicationId "com.github.shadowsocks"
         minSdkVersion rootProject.minSdkVersion
         targetSdkVersion rootProject.sdkVersion
-        versionCode 196
-        versionName "4.3.0"
+        versionCode 200
+        versionName "4.4.0"
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         vectorDrawables.useSupportLibrary true
     }