diff --git a/android/build.gradle b/android/build.gradle
index 95dbd54..ade2dc9 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -27,7 +27,10 @@ def getExtOrIntegerDefault(name) {
 }
 
 android {
-  // namespace 'com.rivereactnative'
+  // Conditional for compatibility with AGP <4.2.
+  if (project.android.hasProperty("namespace")) {
+    namespace = "com.rivereactnative"
+  }
   compileSdkVersion getExtOrIntegerDefault('compileSdkVersion')
   buildToolsVersion getExtOrDefault('buildToolsVersion')
   defaultConfig {