diff --git a/.gitignore b/.gitignore
index 527c983..b4df54f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,4 +7,5 @@ build
 captures
 .externalNativeBuild
 app/src/.deps
-app/src/main/jniLibs
\ No newline at end of file
+app/src/main/jniLibs
+/app/release
diff --git a/.idea/caches/build_file_checksums.ser b/.idea/caches/build_file_checksums.ser
deleted file mode 100644
index de840b0..0000000
Binary files a/.idea/caches/build_file_checksums.ser and /dev/null differ
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
deleted file mode 100644
index 30aa626..0000000
--- a/.idea/codeStyles/Project.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<component name="ProjectCodeStyleConfiguration">
-  <code_scheme name="Project" version="173">
-    <Objective-C-extensions>
-      <file>
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Import" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Macro" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Typedef" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Enum" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Constant" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Global" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Struct" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="FunctionPredecl" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Function" />
-      </file>
-      <class>
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Property" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Synthesize" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InitMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="StaticMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InstanceMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="DeallocMethod" />
-      </class>
-      <extensions>
-        <pair source="cpp" header="h" fileNamingConvention="NONE" />
-        <pair source="c" header="h" fileNamingConvention="NONE" />
-      </extensions>
-    </Objective-C-extensions>
-  </code_scheme>
-</component>
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
deleted file mode 100644
index df593d5..0000000
--- a/.idea/gradle.xml
+++ /dev/null
@@ -1,20 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="GradleSettings">
-    <option name="linkedExternalProjectsSettings">
-      <GradleProjectSettings>
-        <option name="distributionType" value="DEFAULT_WRAPPED" />
-        <option name="externalProjectPath" value="$PROJECT_DIR$" />
-        <option name="modules">
-          <set>
-            <option value="$PROJECT_DIR$" />
-            <option value="$PROJECT_DIR$/app" />
-            <option value="$PROJECT_DIR$/plugin" />
-            <option value="$PROJECT_DIR$/preference-v7" />
-          </set>
-        </option>
-        <option name="resolveModulePerSourceSet" value="false" />
-      </GradleProjectSettings>
-    </option>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
deleted file mode 100644
index 37a7509..0000000
--- a/.idea/misc.xml
+++ /dev/null
@@ -1,9 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" project-jdk-name="1.8" project-jdk-type="JavaSDK">
-    <output url="file://$PROJECT_DIR$/build/classes" />
-  </component>
-  <component name="ProjectType">
-    <option name="id" value="Android" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
deleted file mode 100644
index 3af49f0..0000000
--- a/.idea/modules.xml
+++ /dev/null
@@ -1,11 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/Cloak-android.iml" filepath="$PROJECT_DIR$/Cloak-android.iml" />
-      <module fileurl="file://$PROJECT_DIR$/app/app.iml" filepath="$PROJECT_DIR$/app/app.iml" />
-      <module fileurl="file://$PROJECT_DIR$/plugin/plugin.iml" filepath="$PROJECT_DIR$/plugin/plugin.iml" />
-      <module fileurl="file://$PROJECT_DIR$/preference-v7/preference-v7.iml" filepath="$PROJECT_DIR$/preference-v7/preference-v7.iml" />
-    </modules>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/runConfigurations.xml b/.idea/runConfigurations.xml
deleted file mode 100644
index 7f68460..0000000
--- a/.idea/runConfigurations.xml
+++ /dev/null
@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="RunConfigurationProducerService">
-    <option name="ignoredProducers">
-      <set>
-        <option value="org.jetbrains.plugins.gradle.execution.test.runner.AllInPackageGradleConfigurationProducer" />
-        <option value="org.jetbrains.plugins.gradle.execution.test.runner.TestClassGradleConfigurationProducer" />
-        <option value="org.jetbrains.plugins.gradle.execution.test.runner.TestMethodGradleConfigurationProducer" />
-      </set>
-    </option>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
deleted file mode 100644
index 35eb1dd..0000000
--- a/.idea/vcs.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="" vcs="Git" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/README.md b/README.md
index e9f3131..45a7de8 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,5 @@ Shadowsocks plugin Cloak for Android
 
 ## Build Instructions
 
-1. Edit ndk-bundle\build\tools\make_standalone_toolchain.py, change the line `flags = '-target {} -stdlib=libc++'.format(target)` to `flags = '-target {}'.format(target)` (see https://github.com/golang/go/issues/29706)
-2. Execute `make.sh`
-3. Build with Android Studio
+1. Execute `make.sh`
+2. Build with Android Studio
diff --git a/app/build.gradle b/app/build.gradle
index af6bede..22fd0d0 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -12,10 +12,10 @@ android {
     //buildToolsVersion '26.0.2'
     defaultConfig {
         applicationId "com.github.shadowsocks.plugin.ck_client"
-        minSdkVersion 19
+        minSdkVersion 21
         targetSdkVersion 29
         versionCode 6
-        versionName '2.1.3'
+        versionName '2.1.4'
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
     buildTypes {
@@ -31,11 +31,10 @@ android {
 dependencies {
     implementation fileTree(include: ['*.jar'], dir: 'libs')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
-    implementation 'androidx.appcompat:appcompat:1.0.0'
+    implementation 'androidx.appcompat:appcompat:1.1.0'
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
-    implementation 'androidx.appcompat:appcompat:1.0.0'
-    implementation 'com.github.shadowsocks:plugin:0.1.0'
-    testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'androidx.test:runner:1.1.0'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0'
+    implementation 'com.github.shadowsocks:plugin:1.3.4'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
+    androidTestImplementation 'androidx.test:runner:1.2.0'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
 }
diff --git a/app/src/main/java/com/github/shadowsocks/plugin/ck_client/BinaryProvider.kt b/app/src/main/java/com/github/shadowsocks/plugin/ck_client/BinaryProvider.kt
index 487eb8f..53fe3da 100644
--- a/app/src/main/java/com/github/shadowsocks/plugin/ck_client/BinaryProvider.kt
+++ b/app/src/main/java/com/github/shadowsocks/plugin/ck_client/BinaryProvider.kt
@@ -10,25 +10,20 @@ import java.io.FileNotFoundException
 
 class BinaryProvider : NativePluginProvider() {
     override fun populateFiles(provider: PathProvider) {
-        provider.addPath("ck-client", "755")
+        provider.addPath("ck-client", 0b111101101)
     }
 
     override fun getExecutable(): String {
-        val exec = context.applicationInfo.nativeLibraryDir + "/libck-client.so"
+        val exec = context!!.applicationInfo.nativeLibraryDir + "/libck-client.so"
         Log.d("execPath", exec)
         Log.d("execExists", File(exec).exists().toString())
         return exec
     }
 
-    override fun openFile(uri: Uri?): ParcelFileDescriptor {
-        if (uri == null) {
-            Log.d("URI", "null")
-            throw FileNotFoundException()
-        }
+    override fun openFile(uri: Uri): ParcelFileDescriptor {
         when (uri.path) {
             "/ck-client" -> return ParcelFileDescriptor.open(File(getExecutable()), ParcelFileDescriptor.MODE_READ_ONLY)
             else -> throw FileNotFoundException()
         }
-
     }
-}
\ No newline at end of file
+}
diff --git a/app/src/main/java/com/github/shadowsocks/plugin/ck_client/ConfigFragment.kt b/app/src/main/java/com/github/shadowsocks/plugin/ck_client/ConfigFragment.kt
index e37c81c..67c18d6 100644
--- a/app/src/main/java/com/github/shadowsocks/plugin/ck_client/ConfigFragment.kt
+++ b/app/src/main/java/com/github/shadowsocks/plugin/ck_client/ConfigFragment.kt
@@ -16,8 +16,9 @@ class ConfigFragment : PreferenceFragment() {
     fun onInitializePluginOptions(options: PluginOptions) {
         this._options = options
         val ary = arrayOf(Pair("ProxyMethod","shadowsocks"), Pair("EncryptionMethod","plain"),
-                Pair("UID", ""), Pair("PublicKey",""), Pair("ServerName", "bing.com"),
-                Pair("NumConn","4"), Pair("BrowserSig", "chrome"), Pair("StreamTimeout","300"))
+                Pair("Transport", "direct"), Pair("UID", ""), Pair("PublicKey",""), Pair("ServerName", "bing.com"),
+                Pair("NumConn","4"), Pair("BrowserSig", "chrome"), Pair("StreamTimeout","300"),
+                Pair("KeepAlive", "0"))
         for (element in ary) {
             val key = element.first
             val defaultValue = element.second
@@ -56,4 +57,4 @@ class ConfigFragment : PreferenceFragment() {
         }
         addPreferencesFromResource(R.xml.config)
     }
-}
\ No newline at end of file
+}
diff --git a/app/src/main/res/values/array.xml b/app/src/main/res/values/array.xml
index da18799..a9e17e6 100644
--- a/app/src/main/res/values/array.xml
+++ b/app/src/main/res/values/array.xml
@@ -9,4 +9,8 @@
         <item>aes-gcm</item>
         <item>chacha20-poly1305</item>
     </string-array>
+    <string-array name="transportTypes">
+        <item>direct</item>
+        <item>CDN</item>
+    </string-array>
 </resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 33f8c76..3f7a7c6 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -6,6 +6,8 @@
     <string name="cloak_num_conn">Number of Connections</string>
     <string name="cloak_browser_sig">Browser Signature</string>
     <string name="cloak_encryption_method">Encryption Method</string>
+    <string name="cloak_transport">Transport</string>
     <string name="cloak_proxy_method">Proxy Method</string>
     <string name="cloak_stream_timeout">Stream Timeout</string>
+    <string name="cloak_keepalive">Keep Alive</string>
 </resources>
diff --git a/app/src/main/res/xml/config.xml b/app/src/main/res/xml/config.xml
index 4b5905f..2681cb0 100644
--- a/app/src/main/res/xml/config.xml
+++ b/app/src/main/res/xml/config.xml
@@ -12,10 +12,9 @@
             android:summary="%s"
             android:entries="@array/algorithms"
             android:entryValues="@array/algorithms" />
-        <EditTextPreference
-            android:key="UID"
-            android:persistent="false"
-            android:title="@string/cloak_uid" />
+        <ListPreference android:title="@string/cloak_transport" android:entries="@array/transportTypes"
+            android:entryValues="@array/transportTypes" android:key="Transport" />
+        <EditTextPreference android:key="UID" android:persistent="false" android:title="@string/cloak_uid" />
         <EditTextPreference
             android:key="PublicKey"
             android:persistent="false"
@@ -26,12 +25,6 @@
             android:key="ServerName"
             android:persistent="false"
             android:title="@string/cloak_server_name" />
-        <EditTextPreference
-            android:key="NumConn"
-            android:persistent="false"
-            android:inputType="numberDecimal"
-            android:digits="0123456789"
-            android:title="@string/cloak_num_conn" />
         <ListPreference
             android:key="BrowserSig"
             android:persistent="false"
@@ -39,11 +32,11 @@
             android:summary="%s"
             android:entries="@array/browsers"
             android:entryValues="@array/browsers" />
-        <EditTextPreference
-            android:key="StreamTimeout"
-            android:persistent="false"
-            android:inputType="numberDecimal"
-            android:digits="0123456789"
-            android:title="@string/cloak_stream_timeout"/>
+        <EditTextPreference android:key="NumConn" android:persistent="false" android:inputType="numberDecimal"
+            android:digits="0123456789" android:title="@string/cloak_num_conn" />
+        <EditTextPreference android:key="StreamTimeout" android:persistent="false" android:inputType="numberDecimal"
+            android:digits="0123456789" android:title="@string/cloak_stream_timeout" android:singleLine="true" />
+        <EditTextPreference android:key="KeepAlive" android:persistent="false" android:inputType="numberDecimal"
+            android:digits="0123456789" android:title="@string/cloak_keepalive" android:singleLine="true" />
     </PreferenceCategory>
-</PreferenceScreen>
\ No newline at end of file
+</PreferenceScreen>
diff --git a/build.gradle b/build.gradle
index d8511a9..5de3e80 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,14 +1,14 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.3.11'
+    ext.kotlin_version = '1.3.72'
     repositories {
         google()
         jcenter()
         maven { url "https://jitpack.io" }
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.4.2'
+        classpath 'com.android.tools.build:gradle:3.6.3'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
 
         // NOTE: Do not place your application dependencies here; they belong
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 59edc3c..1b1bc4a 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Sat Mar 07 13:01:33 GMT 2020
-distributionBase=GRADLE_USER_HOME
-distributionPath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME
-zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip
+#Tue May 26 15:42:25 GMT+02:00 2020
+distributionBase=GRADLE_USER_HOME
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.4-all.zip
+distributionPath=wrapper/dists
+zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME