diff --git a/in_app_review/android/build.gradle b/in_app_review/android/build.gradle
index e6594e0..e8b68c9 100644
--- a/in_app_review/android/build.gradle
+++ b/in_app_review/android/build.gradle
@@ -25,6 +25,10 @@ apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
 
 android {
+    // Conditional for compatibility with AGP <4.2.
+    if (project.android.hasProperty("namespace")) {
+      namespace 'dev.britannio.in_app_review'
+    }
     compileSdkVersion 31
 
     compileOptions {
diff --git a/in_app_review/example/android/app/build.gradle b/in_app_review/example/android/app/build.gradle
index 2d7869e..7f7919d 100644
--- a/in_app_review/example/android/app/build.gradle
+++ b/in_app_review/example/android/app/build.gradle
@@ -32,6 +32,7 @@ if (keystorePropertiesFile.exists()) {
 }
 
 android {
+    namespace 'dev.britannio.in_app_review_demo'
     compileSdkVersion flutter.compileSdkVersion
     ndkVersion flutter.ndkVersion