diff --git a/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognitionFlutterPlugin.java b/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognitionFlutterPlugin.java
index 6df5f1cd3..5579d8bc2 100644
--- a/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognitionFlutterPlugin.java
+++ b/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognitionFlutterPlugin.java
@@ -168,7 +168,7 @@ public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, Strin
         // Log.d("onSharedPreferenceChange", result);
         if (key!= null && key.equals(DETECTED_ACTIVITY)) {
             // Log.d(TAG, "Detected activity: " + result);
-            eventSink.success(result);
+            if (eventSink != null) eventSink.success(result);
         }
     }
   }
diff --git a/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognizedService.java b/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognizedService.java
index be4e3b273..9fb0718a7 100644
--- a/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognizedService.java
+++ b/packages/activity_recognition_flutter/android/src/main/java/dk/cachet/activity_recognition_flutter/ActivityRecognizedService.java
@@ -33,7 +33,10 @@ protected void onHandleWork(@Nullable Intent intent) {
     // remove override and make onHandleIntent private.
     private void onHandleIntent(@Nullable Intent intent) {
         ActivityRecognitionResult result = ActivityRecognitionResult.extractResult(intent);
+        if (result == null) return;
+
         List<DetectedActivity> activities = result.getProbableActivities();
+        if (activities == null || activities.isEmpty()) return;
 
         DetectedActivity mostLikely = activities.get(0);
 
@@ -54,6 +57,7 @@ private void onHandleIntent(@Nullable Intent intent) {
         SharedPreferences preferences =
                 getApplicationContext().getSharedPreferences(
                         ActivityRecognitionFlutterPlugin.ACTIVITY_RECOGNITION, MODE_PRIVATE);
+        if (preferences == null) return;
 
         preferences.edit().clear()
                 .putString(