diff --git a/app-to-app-kotlin/app-to-app/build.gradle b/app-to-app-kotlin/app-to-app/build.gradle
index d3d097f..00eaf7f 100644
--- a/app-to-app-kotlin/app-to-app/build.gradle
+++ b/app-to-app-kotlin/app-to-app/build.gradle
@@ -1,6 +1,6 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = "1.5.0"
+    ext.kotlin_version = "1.6.0-M1"
     repositories {
         google()
         mavenCentral()
diff --git a/app-to-phone-kotlin/app-to-phone/build.gradle b/app-to-phone-kotlin/app-to-phone/build.gradle
index 49247a6..074a409 100644
--- a/app-to-phone-kotlin/app-to-phone/build.gradle
+++ b/app-to-phone-kotlin/app-to-phone/build.gradle
@@ -1,6 +1,6 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = "1.5.0"
+    ext.kotlin_version = "1.6.0-M1"
 
     repositories {
         google()
diff --git a/in-app-messaging-kotlin/build.gradle b/in-app-messaging-kotlin/build.gradle
index 1da8c2f..ef6477b 100644
--- a/in-app-messaging-kotlin/build.gradle
+++ b/in-app-messaging-kotlin/build.gradle
@@ -1,6 +1,6 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = "1.5.20"
+    ext.kotlin_version = "1.6.0-M1"
     repositories {
         google()
         mavenCentral()
diff --git a/phone-to-app-kotlin/phone-to-app/build.gradle b/phone-to-app-kotlin/phone-to-app/build.gradle
index d3d097f..00eaf7f 100644
--- a/phone-to-app-kotlin/phone-to-app/build.gradle
+++ b/phone-to-app-kotlin/phone-to-app/build.gradle
@@ -1,6 +1,6 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = "1.5.0"
+    ext.kotlin_version = "1.6.0-M1"
     repositories {
         google()
         mavenCentral()