diff --git a/demos/Android-Demos/PolarSDK-ECG-HR-Demo/app/build.gradle b/demos/Android-Demos/PolarSDK-ECG-HR-Demo/app/build.gradle
index d873a8bb..fac8dc01 100644
--- a/demos/Android-Demos/PolarSDK-ECG-HR-Demo/app/build.gradle
+++ b/demos/Android-Demos/PolarSDK-ECG-HR-Demo/app/build.gradle
@@ -38,7 +38,9 @@ dependencies {
     implementation 'io.reactivex.rxjava3:rxjava:3.0.0'
     implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
     implementation 'androidx.appcompat:appcompat:1.2.0'
+    implementation "androidx.core:core-ktx:1.3.2"
     implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     testImplementation 'junit:junit:4.13.1'
     androidTestImplementation 'androidx.test.ext:junit:1.1.2'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
diff --git a/demos/Android-Demos/PolarSDK-ECG-HR-Demo/build.gradle b/demos/Android-Demos/PolarSDK-ECG-HR-Demo/build.gradle
index d9f7d2f2..cfaa1e7f 100644
--- a/demos/Android-Demos/PolarSDK-ECG-HR-Demo/build.gradle
+++ b/demos/Android-Demos/PolarSDK-ECG-HR-Demo/build.gradle
@@ -1,13 +1,15 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-
+    ext.kotlin_version = '1.4.31'
     repositories {
+        mavenCentral()
         google()
         jcenter()
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:4.1.2'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
 
diff --git a/examples/example-android/androidBleSdkTestApp/app/build.gradle b/examples/example-android/androidBleSdkTestApp/app/build.gradle
index e54c72f6..638aea6f 100644
--- a/examples/example-android/androidBleSdkTestApp/app/build.gradle
+++ b/examples/example-android/androidBleSdkTestApp/app/build.gradle
@@ -1,4 +1,5 @@
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
 
 android {
     compileSdkVersion 29
@@ -35,6 +36,8 @@ dependencies {
     implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
     implementation 'commons-io:commons-io:2.8.0'
     implementation 'androidx.appcompat:appcompat:1.2.0'
+    implementation "androidx.core:core-ktx:1.3.2"
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     testImplementation 'junit:junit:4.13.1'
     androidTestImplementation 'androidx.test.ext:junit:1.1.2'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
diff --git a/examples/example-android/androidBleSdkTestApp/app/src/main/java/polar/com/androidblesdk/MainActivity.java b/examples/example-android/androidBleSdkTestApp/app/src/main/java/polar/com/androidblesdk/MainActivity.java
index 7bf7e496..744d6ba9 100644
--- a/examples/example-android/androidBleSdkTestApp/app/src/main/java/polar/com/androidblesdk/MainActivity.java
+++ b/examples/example-android/androidBleSdkTestApp/app/src/main/java/polar/com/androidblesdk/MainActivity.java
@@ -49,7 +49,7 @@ public class MainActivity extends AppCompatActivity {
     Disposable ppiDisposable;
     Disposable scanDisposable;
     Disposable autoConnectDisposable;
-    String DEVICE_ID = "8C4CAD2D"; //TODO replace with your device id
+    String DEVICE_ID = "8C4CBE21"; //TODO replace with your device id
     PolarExerciseEntry exerciseEntry;
 
     @Override
diff --git a/examples/example-android/androidBleSdkTestApp/build.gradle b/examples/example-android/androidBleSdkTestApp/build.gradle
index d9f7d2f2..cfaa1e7f 100644
--- a/examples/example-android/androidBleSdkTestApp/build.gradle
+++ b/examples/example-android/androidBleSdkTestApp/build.gradle
@@ -1,13 +1,15 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-
+    ext.kotlin_version = '1.4.31'
     repositories {
+        mavenCentral()
         google()
         jcenter()
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:4.1.2'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }