diff --git a/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabase.java b/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabase.java
index f07a3759..df7358ea 100644
--- a/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabase.java
+++ b/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabase.java
@@ -73,9 +73,10 @@ public class RNFirebaseDatabase extends ReactContextBaseJavaModule {
    * @param state
    */
   @ReactMethod
-  public void keepSynced(String appName, String path, Boolean state) {
-    // TODO: Needs to take into account modifiers as well as just the path
-    getReferenceForAppPath(appName, path).keepSynced(state);
+  public void keepSynced(String appName, int id, String path, ReadableArray modifiers, Boolean state) {
+    getInternalReferenceForApp(appName, id, path, modifiers, false)
+      .getQuery()
+      .keepSynced(state);
   }
 
 
@@ -406,8 +407,6 @@ public class RNFirebaseDatabase extends ReactContextBaseJavaModule {
 
   }
 
-
-
   /*
    * INTERNALS/UTILS
    */
@@ -441,6 +440,11 @@ public class RNFirebaseDatabase extends ReactContextBaseJavaModule {
     return "RNFirebaseDatabase";
   }
 
+  /**
+   * React Native constants for RNFirebaseDatabase
+   *
+   * @return
+   */
   @Override
   public Map<String, Object> getConstants() {
     final Map<String, Object> constants = new HashMap<>();
@@ -471,6 +475,8 @@ public class RNFirebaseDatabase extends ReactContextBaseJavaModule {
   }
 
   /**
+   * Return an existing or create a new RNFirebaseDatabaseReference instance.
+   *
    * @param appName
    * @param refId
    * @param path
@@ -520,6 +526,13 @@ public class RNFirebaseDatabase extends ReactContextBaseJavaModule {
     return service.toUpperCase() + "/" + code.toUpperCase();
   }
 
+  /**
+   * Convert as firebase DatabaseError instance into a writable map
+   * with the correct web-like error codes.
+   *
+   * @param nativeError
+   * @return
+   */
   static WritableMap getJSError(DatabaseError nativeError) {
     WritableMap errorMap = Arguments.createMap();
     errorMap.putInt("nativeErrorCode", nativeError.getCode());
diff --git a/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabaseReference.java b/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabaseReference.java
index 714999f1..c955966c 100644
--- a/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabaseReference.java
+++ b/android/src/main/java/io/invertase/firebase/database/RNFirebaseDatabaseReference.java
@@ -33,6 +33,10 @@ public class RNFirebaseDatabaseReference {
   private SparseArray<ChildEventListener> childEventListeners;
   private SparseArray<ValueEventListener> valueEventListeners;
 
+  Query getQuery() {
+    return query;
+  }
+
   /**
    * @param context
    * @param app
@@ -45,11 +49,8 @@ public class RNFirebaseDatabaseReference {
     appName = app;
     path = refPath;
     reactContext = context;
-
-    // todo only create if needed
     childEventListeners = new SparseArray<ChildEventListener>();
     valueEventListeners = new SparseArray<ValueEventListener>();
-
     query = buildDatabaseQueryAtPathAndModifiers(path, modifiersArray);
   }
 
@@ -58,7 +59,7 @@ public class RNFirebaseDatabaseReference {
    *
    * @param promise
    */
-  void addOnceValueEventListener(final Promise promise) {
+  private void addOnceValueEventListener(final Promise promise) {
     ValueEventListener onceValueEventListener = new ValueEventListener() {
       @Override
       public void onDataChange(DataSnapshot dataSnapshot) {
@@ -83,7 +84,7 @@ public class RNFirebaseDatabaseReference {
    * @param eventName
    * @param promise
    */
-  void addChildOnceEventListener(final String eventName, final Promise promise) {
+  private void addChildOnceEventListener(final String eventName, final Promise promise) {
     ChildEventListener childEventListener = new ChildEventListener() {
       @Override
       public void onChildAdded(DataSnapshot dataSnapshot, String previousChildName) {
@@ -132,12 +133,16 @@ public class RNFirebaseDatabaseReference {
   }
 
 
+  /**
+   * Handles a React Native JS 'on' request and initializes listeners.
+   * @param eventName
+   */
   void on(String eventName) {
 
   }
 
   /**
-   *
+   * Handles a React Native JS 'once' request.
    * @param eventName
    * @param promise
    */