diff --git a/android/src/main/java/com/squareup/sdk/reader/flutter/SquareReaderSdkFlutterPlugin.java b/android/src/main/java/com/squareup/sdk/reader/flutter/SquareReaderSdkFlutterPlugin.java
index c57d878..9418006 100644
--- a/android/src/main/java/com/squareup/sdk/reader/flutter/SquareReaderSdkFlutterPlugin.java
+++ b/android/src/main/java/com/squareup/sdk/reader/flutter/SquareReaderSdkFlutterPlugin.java
@@ -157,7 +157,12 @@ private void initializeReaderSdk() {
       return;
     }
 
-    ReaderSdk.initialize(currentActivity.getApplication());
-    sdkInitialized = true;
+    try {
+      ReaderSdk.initialize(currentActivity.getApplication());
+      sdkInitialized = true;
+    } catch (IllegalStateException e) {
+      // allow double-initialization; devs _should_ init in Application.onCreate,
+      // but to be non-breaking we try here also in case they didn't.
+    }
   }
-}
+}
\ No newline at end of file
diff --git a/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.kt b/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.java
similarity index 81%
rename from example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.kt
rename to example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.java
index d20f9ef..105a6b3 100644
--- a/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.kt
+++ b/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainActivity.java
@@ -15,8 +15,10 @@
 */
 package com.example.flutter.squareup.sdk.reader;
 
-import io.flutter.embedding.android.FlutterActivity
+import androidx.annotation.NonNull;
 
-class MainActivity: FlutterActivity() {
+import io.flutter.embedding.android.FlutterActivity;
+
+public class MainActivity extends FlutterActivity {
 }
 
diff --git a/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.kt b/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.java
similarity index 64%
rename from example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.kt
rename to example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.java
index bddc3fe..1eb228c 100644
--- a/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.kt
+++ b/example/android/app/src/main/java/com/example/flutter/squareup/sdk/reader/MainApplication.java
@@ -15,7 +15,18 @@
 */
 package com.example.flutter.squareup.sdk.reader;
 
-import io.flutter.app.FlutterApplication
+import com.squareup.sdk.reader.ReaderSdk;
+import io.flutter.app.FlutterApplication;
 
-class MainApplication: FlutterApplication() {
+import io.flutter.view.FlutterMain;
+
+
+public class MainApplication extends FlutterApplication {
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        ReaderSdk.initialize(this);
+        FlutterMain.startInitialization(this);
+    }
 }
diff --git a/pubspec.yaml b/pubspec.yaml
index f1b4b4a..2b7c158 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: square_reader_sdk
 description: An open source Flutter plugin for calling Square’s native Reader SDK implementations to take in-person payments on iOS and Android.
-version: 4.0.0
+version: 4.0.1
 homepage: https://github.com/square/reader-sdk-flutter-plugin
 
 environment: