diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 0000000..30aa626
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,29 @@
+<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/encodings.xml b/.idea/encodings.xml
deleted file mode 100644
index 97626ba..0000000
--- a/.idea/encodings.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Encoding">
-    <file url="PROJECT" charset="UTF-8" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index cc72de3..af0bbdd 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,49 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="NullableNotNullManager">
-    <option name="myDefaultNullable" value="android.support.annotation.Nullable" />
-    <option name="myDefaultNotNull" value="android.support.annotation.NonNull" />
-    <option name="myNullables">
-      <value>
-        <list size="4">
-          <item index="0" class="java.lang.String" itemvalue="org.jetbrains.annotations.Nullable" />
-          <item index="1" class="java.lang.String" itemvalue="javax.annotation.Nullable" />
-          <item index="2" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.Nullable" />
-          <item index="3" class="java.lang.String" itemvalue="android.support.annotation.Nullable" />
-        </list>
-      </value>
-    </option>
-    <option name="myNotNulls">
-      <value>
-        <list size="4">
-          <item index="0" class="java.lang.String" itemvalue="org.jetbrains.annotations.NotNull" />
-          <item index="1" class="java.lang.String" itemvalue="javax.annotation.Nonnull" />
-          <item index="2" class="java.lang.String" itemvalue="edu.umd.cs.findbugs.annotations.NonNull" />
-          <item index="3" class="java.lang.String" itemvalue="android.support.annotation.NonNull" />
-        </list>
-      </value>
-    </option>
+  <component name="CMakeSettings">
+    <configurations>
+      <configuration PROFILE_NAME="Debug" CONFIG_NAME="Debug" />
+    </configurations>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" default="true" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+  <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>
-  <component name="masterDetails">
-    <states>
-      <state key="ProjectJDKs.UI">
-        <settings>
-          <last-edited>1.8</last-edited>
-          <splitter-proportions>
-            <option name="proportions">
-              <list>
-                <option value="0.2" />
-              </list>
-            </option>
-          </splitter-proportions>
-        </settings>
-      </state>
-    </states>
-  </component>
 </project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
index 94a25f7..35eb1dd 100644
--- a/.idea/vcs.xml
+++ b/.idea/vcs.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="" vcs="Git" />
   </component>
 </project>
\ No newline at end of file
diff --git a/README.md b/README.md
index 376591e..9d2e612 100644
--- a/README.md
+++ b/README.md
@@ -8,9 +8,9 @@ Bluetooth chat app written purely in Kotlin.
 # Prerequisite
 
 <ul>
-<li>Android Studio 3.0</li>
+<li>Android Studio 3.3.2</li>
 <li>Gradle Plugin v3.0.0-beta1</li>
-<li>Kotlin Plugin v1.1.3-2</li>
+<li>Kotlin Plugin v1.3.21</li>
 </ul>
 
 # Min SDK
diff --git a/app/build.gradle b/app/build.gradle
index da24f70..bf4a146 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -6,7 +6,7 @@ apply plugin: 'kotlin-android-extensions'
 
 android {
     compileSdkVersion 26
-    buildToolsVersion "25.0.3"
+    buildToolsVersion "28.0.3"
     defaultConfig {
         applicationId "com.webianks.bluechat"
         minSdkVersion 21
@@ -28,7 +28,7 @@ dependencies {
     androidTestImplementation ('com.android.support.test.espresso:espresso-core:2.2.2', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    implementation"org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
+    implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     implementation 'com.android.support:appcompat-v7:26.0.1'
     testImplementation 'junit:junit:4.12'
     implementation 'com.android.support.constraint:constraint-layout:1.0.2'
diff --git a/app/src/main/java/com/webianks/bluechat/BluetoothChatService.kt b/app/src/main/java/com/webianks/bluechat/BluetoothChatService.kt
index 783bf2d..bd70dbe 100644
--- a/app/src/main/java/com/webianks/bluechat/BluetoothChatService.kt
+++ b/app/src/main/java/com/webianks/bluechat/BluetoothChatService.kt
@@ -32,8 +32,10 @@ class BluetoothChatService(context: Context, handler: Handler){
     private val  TAG: String = javaClass.simpleName
 
     // Unique UUID for this application
-    private val MY_UUID_SECURE = UUID.fromString("29621b37-e817-485a-a258-52da5261421a")
-    private val MY_UUID_INSECURE = UUID.fromString("d620cd2b-e0a4-435b-b02e-40324d57195b")
+//    private val MY_UUID_SECURE = UUID.fromString("29621b37-e817-485a-a258-52da5261421a")
+//    private val MY_UUID_INSECURE = UUID.fromString("d620cd2b-e0a4-435b-b02e-40324d57195b")
+    private val MY_UUID_SECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB") // SerialPortServiceClass_UUID
+    private val MY_UUID_INSECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB") // SerialPortServiceClass_UUID
 
 
     // Name for the SDP record when creating server socket
diff --git a/build.gradle b/build.gradle
index 0597a54..aa2b135 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,13 +1,13 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.1.3-2'
+    ext.kotlin_version = '1.3.21'
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.0-beta5'
+        classpath 'com.android.tools.build:gradle:3.3.2'
         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 49214a4..2d8c1fa 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Mon Sep 11 23:34:33 IST 2017
+#Tue Apr 02 22:13:45 JST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-all.zip