diff --git a/packages/firebase_auth/README.md b/packages/firebase_auth/README.md
index 2a2d577c1758..ea654cc74a07 100755
--- a/packages/firebase_auth/README.md
+++ b/packages/firebase_auth/README.md
@@ -55,7 +55,7 @@ import 'package:firebase_auth/firebase_auth.dart';
 Initialize `GoogleSignIn` and `FirebaseAuth`:
 ```dart
 final GoogleSignIn _googleSignIn = GoogleSignIn();
-final FirebaseAuth _auth = FirebaseAuth();
+final FirebaseAuth _auth = FirebaseAuth.instance;
 ```
 
 You can now use the Firebase `_auth` to authenticate in your Dart code, e.g.
diff --git a/packages/firebase_auth/android/src/main/java/io/flutter/plugins/firebaseauth/FirebaseAuthPlugin.java b/packages/firebase_auth/android/src/main/java/io/flutter/plugins/firebaseauth/FirebaseAuthPlugin.java
index b9e936c69151..dd932794a139 100755
--- a/packages/firebase_auth/android/src/main/java/io/flutter/plugins/firebaseauth/FirebaseAuthPlugin.java
+++ b/packages/firebase_auth/android/src/main/java/io/flutter/plugins/firebaseauth/FirebaseAuthPlugin.java
@@ -29,6 +29,7 @@
 /** Flutter plugin for Firebase Auth. */
 public class FirebaseAuthPlugin implements MethodCallHandler {
   private final PluginRegistry.Registrar registrar;
+  private final FirebaseAuth firebaseAuth;
   private final SparseArray<FirebaseAuth.AuthStateListener> authStateListeners =
       new SparseArray<>();
   private final SparseArray<PhoneAuthProvider.ForceResendingToken> forceResendingTokens =
@@ -50,98 +51,92 @@ private FirebaseAuthPlugin(PluginRegistry.Registrar registrar, MethodChannel cha
     this.registrar = registrar;
     this.channel = channel;
     FirebaseApp.initializeApp(registrar.context());
-  }
-
-  private FirebaseAuth getAuth(MethodCall call) {
-    Map<String, Object> arguments = (Map<String, Object>) call.arguments;
-    String appName = (String) arguments.get("app");
-    FirebaseApp app = FirebaseApp.getInstance(appName);
-    return FirebaseAuth.getInstance(app);
+    this.firebaseAuth = FirebaseAuth.getInstance();
   }
 
   @Override
   public void onMethodCall(MethodCall call, Result result) {
     switch (call.method) {
       case "currentUser":
-        handleCurrentUser(call, result, getAuth(call));
+        handleCurrentUser(call, result);
         break;
       case "signInAnonymously":
-        handleSignInAnonymously(call, result, getAuth(call));
+        handleSignInAnonymously(call, result);
         break;
       case "createUserWithEmailAndPassword":
-        handleCreateUserWithEmailAndPassword(call, result, getAuth(call));
+        handleCreateUserWithEmailAndPassword(call, result);
         break;
       case "fetchProvidersForEmail":
-        handleFetchProvidersForEmail(call, result, getAuth(call));
+        handleFetchProvidersForEmail(call, result);
         break;
       case "sendPasswordResetEmail":
-        handleSendPasswordResetEmail(call, result, getAuth(call));
+        handleSendPasswordResetEmail(call, result);
         break;
       case "sendEmailVerification":
-        handleSendEmailVerification(call, result, getAuth(call));
+        handleSendEmailVerification(call, result);
         break;
       case "reload":
-        handleReload(call, result, getAuth(call));
+        handleReload(call, result);
         break;
       case "delete":
-        handleDelete(call, result, getAuth(call));
+        handleDelete(call, result);
         break;
       case "signInWithEmailAndPassword":
-        handleSignInWithEmailAndPassword(call, result, getAuth(call));
+        handleSignInWithEmailAndPassword(call, result);
         break;
       case "signInWithGoogle":
-        handleSignInWithGoogle(call, result, getAuth(call));
+        handleSignInWithGoogle(call, result);
         break;
       case "signInWithCustomToken":
-        handleSignInWithCustomToken(call, result, getAuth(call));
+        handleSignInWithCustomToken(call, result);
         break;
       case "signInWithFacebook":
-        handleSignInWithFacebook(call, result, getAuth(call));
+        handleSignInWithFacebook(call, result);
         break;
       case "signInWithTwitter":
-        handleSignInWithTwitter(call, result, getAuth(call));
+        handleSignInWithTwitter(call, result);
         break;
       case "signOut":
-        handleSignOut(call, result, getAuth(call));
+        handleSignOut(call, result);
         break;
       case "getIdToken":
-        handleGetToken(call, result, getAuth(call));
+        handleGetToken(call, result);
         break;
       case "linkWithEmailAndPassword":
-        handleLinkWithEmailAndPassword(call, result, getAuth(call));
+        handleLinkWithEmailAndPassword(call, result);
         break;
       case "linkWithGoogleCredential":
-        handleLinkWithGoogleCredential(call, result, getAuth(call));
+        handleLinkWithGoogleCredential(call, result);
         break;
       case "linkWithFacebookCredential":
-        handleLinkWithFacebookCredential(call, result, getAuth(call));
+        handleLinkWithFacebookCredential(call, result);
         break;
       case "linkWithTwitterCredential":
-        handleLinkWithTwitterCredential(call, result, getAuth(call));
+        handleLinkWithTwitterCredential(call, result);
         break;
       case "updateEmail":
-        handleUpdateEmail(call, result, getAuth(call));
+        handleUpdateEmail(call, result);
         break;
       case "updatePassword":
-        handleUpdatePassword(call, result, getAuth(call));
+        handleUpdatePassword(call, result);
         break;
       case "updateProfile":
-        handleUpdateProfile(call, result, getAuth(call));
+        handleUpdateProfile(call, result);
         break;
       case "startListeningAuthState":
-        handleStartListeningAuthState(call, result, getAuth(call));
+        handleStartListeningAuthState(call, result);
         break;
       case "stopListeningAuthState":
-        handleStopListeningAuthState(call, result, getAuth(call));
+        handleStopListeningAuthState(call, result);
         break;
       case "verifyPhoneNumber":
-        handleVerifyPhoneNumber(call, result, getAuth(call));
+        handleVerifyPhoneNumber(call, result);
         break;
       case "signInWithPhoneNumber":
-        handleSignInWithPhoneNumber(call, result, getAuth(call));
+        handleSignInWithPhoneNumber(call, result);
         break;
       case "setLanguageCode":
-        handleSetLanguageCode(call, result, getAuth(call));
+        handleSetLanguageCode(call, result);
         break;
       default:
         result.notImplemented();
@@ -149,8 +144,7 @@ public void onMethodCall(MethodCall call, Result result) {
     }
   }
 
-  private void handleSignInWithPhoneNumber(
-      MethodCall call, Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInWithPhoneNumber(MethodCall call, Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String verificationId = arguments.get("verificationId");
@@ -163,8 +157,7 @@ private void handleSignInWithPhoneNumber(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleVerifyPhoneNumber(
-      MethodCall call, Result result, final FirebaseAuth firebaseAuth) {
+  private void handleVerifyPhoneNumber(MethodCall call, Result result) {
     @SuppressWarnings("unchecked")
     final int handle = call.argument("handle");
     String phoneNumber = call.argument("phoneNumber");
@@ -257,8 +250,7 @@ private Map<String, Object> getVerifyPhoneNumberExceptionMap(FirebaseException e
     return exceptionMap;
   }
 
-  private void handleLinkWithEmailAndPassword(
-      MethodCall call, Result result, FirebaseAuth firebaseAuth) {
+  private void handleLinkWithEmailAndPassword(MethodCall call, Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String email = arguments.get("email");
@@ -271,23 +263,26 @@ private void handleLinkWithEmailAndPassword(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleCurrentUser(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
-    FirebaseUser user = firebaseAuth.getCurrentUser();
-    if (user == null) {
-      result.success(null);
-      return;
-    }
-    Map<String, Object> userMap = mapFromUser(user);
-    result.success(userMap);
+  private void handleCurrentUser(MethodCall call, final Result result) {
+    final FirebaseAuth.AuthStateListener listener =
+        new FirebaseAuth.AuthStateListener() {
+          @Override
+          public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
+            firebaseAuth.removeAuthStateListener(this);
+            FirebaseUser user = firebaseAuth.getCurrentUser();
+            Map<String, Object> userMap = mapFromUser(user);
+            result.success(userMap);
+          }
+        };
+
+    firebaseAuth.addAuthStateListener(listener);
   }
 
-  private void handleSignInAnonymously(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInAnonymously(MethodCall call, final Result result) {
     firebaseAuth.signInAnonymously().addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleCreateUserWithEmailAndPassword(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleCreateUserWithEmailAndPassword(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String email = arguments.get("email");
@@ -298,8 +293,7 @@ private void handleCreateUserWithEmailAndPassword(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleFetchProvidersForEmail(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleFetchProvidersForEmail(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String email = arguments.get("email");
@@ -309,8 +303,7 @@ private void handleFetchProvidersForEmail(
         .addOnCompleteListener(new ProvidersCompleteListener(result));
   }
 
-  private void handleSendPasswordResetEmail(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSendPasswordResetEmail(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String email = arguments.get("email");
@@ -320,23 +313,28 @@ private void handleSendPasswordResetEmail(
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleSendEmailVerification(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSendEmailVerification(MethodCall call, final Result result) {
     firebaseAuth
         .getCurrentUser()
         .sendEmailVerification()
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleReload(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleReload(MethodCall call, final Result result) {
     firebaseAuth
         .getCurrentUser()
         .reload()
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleSignInWithEmailAndPassword(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleDelete(MethodCall call, final Result result) {
+    firebaseAuth
+        .getCurrentUser()
+        .delete()
+        .addOnCompleteListener(new TaskVoidCompleteListener(result));
+  }
+
+  private void handleSignInWithEmailAndPassword(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String email = arguments.get("email");
@@ -347,15 +345,7 @@ private void handleSignInWithEmailAndPassword(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleDelete(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
-    firebaseAuth
-        .getCurrentUser()
-        .delete()
-        .addOnCompleteListener(new TaskVoidCompleteListener(result));
-  }
-
-  private void handleSignInWithGoogle(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInWithGoogle(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String idToken = arguments.get("idToken");
@@ -366,8 +356,7 @@ private void handleSignInWithGoogle(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleLinkWithGoogleCredential(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleLinkWithGoogleCredential(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String idToken = arguments.get("idToken");
@@ -379,8 +368,7 @@ private void handleLinkWithGoogleCredential(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleLinkWithFacebookCredential(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleLinkWithFacebookCredential(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String accessToken = arguments.get("accessToken");
@@ -391,8 +379,7 @@ private void handleLinkWithFacebookCredential(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleLinkWithTwitterCredential(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleLinkWithTwitterCredential(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String authToken = arguments.get("authToken");
@@ -404,8 +391,7 @@ private void handleLinkWithTwitterCredential(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleSignInWithFacebook(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInWithFacebook(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String accessToken = arguments.get("accessToken");
@@ -415,8 +401,7 @@ private void handleSignInWithFacebook(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleSignInWithTwitter(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInWithTwitter(MethodCall call, final Result result) {
     String authToken = call.argument("authToken");
     String authTokenSecret = call.argument("authTokenSecret");
     AuthCredential credential = TwitterAuthProvider.getCredential(authToken, authTokenSecret);
@@ -425,8 +410,7 @@ private void handleSignInWithTwitter(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleSignInWithCustomToken(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignInWithCustomToken(MethodCall call, final Result result) {
     Map<String, String> arguments = call.arguments();
     String token = arguments.get("token");
     firebaseAuth
@@ -434,12 +418,12 @@ private void handleSignInWithCustomToken(
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
-  private void handleSignOut(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSignOut(MethodCall call, final Result result) {
     firebaseAuth.signOut();
     result.success(null);
   }
 
-  private void handleGetToken(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleGetToken(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, Boolean> arguments = (Map<String, Boolean>) call.arguments;
     boolean refresh = arguments.get("refresh");
@@ -459,7 +443,7 @@ public void onComplete(@NonNull Task<GetTokenResult> task) {
             });
   }
 
-  private void handleUpdateEmail(MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleUpdateEmail(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     firebaseAuth
@@ -468,8 +452,7 @@ private void handleUpdateEmail(MethodCall call, final Result result, FirebaseAut
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleUpdatePassword(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleUpdatePassword(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     firebaseAuth
@@ -478,8 +461,7 @@ private void handleUpdatePassword(
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleUpdateProfile(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleUpdateProfile(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
 
@@ -497,8 +479,7 @@ private void handleUpdateProfile(
         .addOnCompleteListener(new TaskVoidCompleteListener(result));
   }
 
-  private void handleStartListeningAuthState(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleStartListeningAuthState(MethodCall call, final Result result) {
     final int handle = nextHandle++;
     FirebaseAuth.AuthStateListener listener =
         new FirebaseAuth.AuthStateListener() {
@@ -515,19 +496,18 @@ public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
             channel.invokeMethod("onAuthStateChanged", Collections.unmodifiableMap(map));
           }
         };
-    firebaseAuth.addAuthStateListener(listener);
+    FirebaseAuth.getInstance().addAuthStateListener(listener);
     authStateListeners.append(handle, listener);
     result.success(handle);
   }
 
-  private void handleStopListeningAuthState(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleStopListeningAuthState(MethodCall call, final Result result) {
     Map<String, Integer> arguments = call.arguments();
     Integer id = arguments.get("id");
 
     FirebaseAuth.AuthStateListener listener = authStateListeners.get(id);
     if (listener != null) {
-      firebaseAuth.removeAuthStateListener(listener);
+      FirebaseAuth.getInstance().removeAuthStateListener(listener);
       authStateListeners.remove(id);
       result.success(null);
     } else {
@@ -538,8 +518,7 @@ private void handleStopListeningAuthState(
     }
   }
 
-  private void handleSetLanguageCode(
-      MethodCall call, final Result result, FirebaseAuth firebaseAuth) {
+  private void handleSetLanguageCode(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;
     String language = arguments.get("language");
diff --git a/packages/firebase_auth/example/ios/Runner.xcodeproj/project.pbxproj b/packages/firebase_auth/example/ios/Runner.xcodeproj/project.pbxproj
old mode 100644
new mode 100755
index db497a45aa5b..eebc126be7ae
--- a/packages/firebase_auth/example/ios/Runner.xcodeproj/project.pbxproj
+++ b/packages/firebase_auth/example/ios/Runner.xcodeproj/project.pbxproj
@@ -8,8 +8,8 @@
 
 /* Begin PBXBuildFile section */
 		0690AA46E879ED4CF7B7AEB4 /* libPods-Runner.a in Frameworks */ = {isa = PBXBuildFile; fileRef = A6A0D603F1BEC33B95572EC3 /* libPods-Runner.a */; };
-		2D5378261FAA1A9400D5DBA9 /* flutter_assets in Resources */ = {isa = PBXBuildFile; fileRef = 2D5378251FAA1A9400D5DBA9 /* flutter_assets */; };
 		3B3967161E833CAA004F5970 /* AppFrameworkInfo.plist in Resources */ = {isa = PBXBuildFile; fileRef = 3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */; };
+		2D5378261FAA1A9400D5DBA9 /* flutter_assets in Resources */ = {isa = PBXBuildFile; fileRef = 2D5378251FAA1A9400D5DBA9 /* flutter_assets */; };
 		3B80C3941E831B6300D905FE /* App.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 3B80C3931E831B6300D905FE /* App.framework */; };
 		3B80C3951E831B6300D905FE /* App.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 3B80C3931E831B6300D905FE /* App.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		5C97AA501EC3F2C300D441D1 /* GeneratedPluginRegistrant.m in Sources */ = {isa = PBXBuildFile; fileRef = 5C97AA4F1EC3F2C300D441D1 /* GeneratedPluginRegistrant.m */; };
@@ -41,8 +41,8 @@
 /* End PBXCopyFilesBuildPhase section */
 
 /* Begin PBXFileReference section */
-		2D5378251FAA1A9400D5DBA9 /* flutter_assets */ = {isa = PBXFileReference; lastKnownFileType = folder; name = flutter_assets; path = Flutter/flutter_assets; sourceTree = SOURCE_ROOT; };
 		3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; name = AppFrameworkInfo.plist; path = Flutter/AppFrameworkInfo.plist; sourceTree = "<group>"; };
+		2D5378251FAA1A9400D5DBA9 /* flutter_assets */ = {isa = PBXFileReference; lastKnownFileType = folder; name = flutter_assets; path = Flutter/flutter_assets; sourceTree = SOURCE_ROOT; };
 		3B80C3931E831B6300D905FE /* App.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = App.framework; path = Flutter/App.framework; sourceTree = "<group>"; };
 		5C97AA4E1EC3F2C300D441D1 /* GeneratedPluginRegistrant.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = GeneratedPluginRegistrant.h; sourceTree = "<group>"; };
 		5C97AA4F1EC3F2C300D441D1 /* GeneratedPluginRegistrant.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GeneratedPluginRegistrant.m; sourceTree = "<group>"; };
@@ -253,8 +253,7 @@
 			);
 			name = "[CP] Copy Pods Resources";
 			outputPaths = (
-				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GTMOAuth2ViewTouch.nib",
-				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GoogleSignIn.bundle",
+				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}",
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
@@ -268,7 +267,7 @@
 			);
 			inputPaths = (
 				"${SRCROOT}/Pods/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh",
-				"${PODS_ROOT}/../.symlinks/flutter/ios/Flutter.framework",
+				"${PODS_ROOT}/../../../../../../../flutter/bin/cache/artifacts/engine/ios/Flutter.framework",
 			);
 			name = "[CP] Embed Pods Frameworks";
 			outputPaths = (
diff --git a/packages/firebase_auth/example/lib/main.dart b/packages/firebase_auth/example/lib/main.dart
index bc103e2de85e..2dce1c78b61a 100755
--- a/packages/firebase_auth/example/lib/main.dart
+++ b/packages/firebase_auth/example/lib/main.dart
@@ -9,7 +9,7 @@ import 'package:flutter/material.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'package:google_sign_in/google_sign_in.dart';
 
-final FirebaseAuth _auth = FirebaseAuth();
+final FirebaseAuth _auth = FirebaseAuth.instance;
 final GoogleSignIn _googleSignIn = GoogleSignIn();
 
 void main() {
diff --git a/packages/firebase_auth/ios/Classes/FirebaseAuthPlugin.m b/packages/firebase_auth/ios/Classes/FirebaseAuthPlugin.m
index e45ee9ad3c71..5bdf4b929992 100644
--- a/packages/firebase_auth/ios/Classes/FirebaseAuthPlugin.m
+++ b/packages/firebase_auth/ios/Classes/FirebaseAuthPlugin.m
@@ -59,20 +59,15 @@ - (instancetype)init {
   return self;
 }
 
-- (FIRAuth *_Nullable)getAuth:(NSDictionary *)args {
-  NSString *appName = [args objectForKey:@"app"];
-  return [FIRAuth authWithApp:[FIRApp appNamed:appName]];
-}
-
 - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result {
   if ([@"currentUser" isEqualToString:call.method]) {
-    id __block listener = [[self getAuth:call.arguments]
+    id __block listener = [[FIRAuth auth]
         addAuthStateDidChangeListener:^(FIRAuth *_Nonnull auth, FIRUser *_Nullable user) {
           [self sendResult:result forUser:user error:nil];
           [auth removeAuthStateDidChangeListener:listener];
         }];
   } else if ([@"signInAnonymously" isEqualToString:call.method]) {
-    [[self getAuth:call.arguments]
+    [[FIRAuth auth]
         signInAnonymouslyWithCompletion:^(FIRAuthDataResult *dataResult, NSError *error) {
           [self sendResult:result forUser:dataResult.user error:error];
         }];
@@ -81,74 +76,69 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
     NSString *accessToken = call.arguments[@"accessToken"];
     FIRAuthCredential *credential =
         [FIRGoogleAuthProvider credentialWithIDToken:idToken accessToken:accessToken];
-    [[self getAuth:call.arguments] signInWithCredential:credential
-                                             completion:^(FIRUser *user, NSError *error) {
-                                               [self sendResult:result forUser:user error:error];
-                                             }];
+    [[FIRAuth auth] signInWithCredential:credential
+                              completion:^(FIRUser *user, NSError *error) {
+                                [self sendResult:result forUser:user error:error];
+                              }];
   } else if ([@"signInWithFacebook" isEqualToString:call.method]) {
     NSString *accessToken = call.arguments[@"accessToken"];
     FIRAuthCredential *credential = [FIRFacebookAuthProvider credentialWithAccessToken:accessToken];
-    [[self getAuth:call.arguments] signInWithCredential:credential
-                                             completion:^(FIRUser *user, NSError *error) {
-                                               [self sendResult:result forUser:user error:error];
-                                             }];
+    [[FIRAuth auth] signInWithCredential:credential
+                              completion:^(FIRUser *user, NSError *error) {
+                                [self sendResult:result forUser:user error:error];
+                              }];
   } else if ([@"signInWithTwitter" isEqualToString:call.method]) {
     NSString *authToken = call.arguments[@"authToken"];
     NSString *authTokenSecret = call.arguments[@"authTokenSecret"];
     FIRAuthCredential *credential =
         [FIRTwitterAuthProvider credentialWithToken:authToken secret:authTokenSecret];
-    [[self getAuth:call.arguments] signInWithCredential:credential
-                                             completion:^(FIRUser *user, NSError *error) {
-                                               [self sendResult:result forUser:user error:error];
-                                             }];
+    [[FIRAuth auth] signInWithCredential:credential
+                              completion:^(FIRUser *user, NSError *error) {
+                                [self sendResult:result forUser:user error:error];
+                              }];
   } else if ([@"createUserWithEmailAndPassword" isEqualToString:call.method]) {
     NSString *email = call.arguments[@"email"];
     NSString *password = call.arguments[@"password"];
-    [[self getAuth:call.arguments]
-        createUserWithEmail:email
-                   password:password
-                 completion:^(FIRAuthDataResult *dataResult, NSError *error) {
-                   [self sendResult:result forUser:dataResult.user error:error];
-                 }];
+    [[FIRAuth auth] createUserWithEmail:email
+                               password:password
+                             completion:^(FIRAuthDataResult *dataResult, NSError *error) {
+                               [self sendResult:result forUser:dataResult.user error:error];
+                             }];
   } else if ([@"fetchProvidersForEmail" isEqualToString:call.method]) {
     NSString *email = call.arguments[@"email"];
-    [[self getAuth:call.arguments]
-        fetchProvidersForEmail:email
-                    completion:^(NSArray<NSString *> *providers, NSError *error) {
-                      [self sendResult:result forProviders:providers error:error];
-                    }];
+    [[FIRAuth auth] fetchProvidersForEmail:email
+                                completion:^(NSArray<NSString *> *providers, NSError *error) {
+                                  [self sendResult:result forProviders:providers error:error];
+                                }];
   } else if ([@"sendEmailVerification" isEqualToString:call.method]) {
-    [[self getAuth:call.arguments].currentUser
-        sendEmailVerificationWithCompletion:^(NSError *_Nullable error) {
-          [self sendResult:result forProviders:nil error:error];
-        }];
+    [[FIRAuth auth].currentUser sendEmailVerificationWithCompletion:^(NSError *_Nullable error) {
+      [self sendResult:result forProviders:nil error:error];
+    }];
   } else if ([@"reload" isEqualToString:call.method]) {
-    [[self getAuth:call.arguments].currentUser reloadWithCompletion:^(NSError *_Nullable error) {
+    [[FIRAuth auth].currentUser reloadWithCompletion:^(NSError *_Nullable error) {
       [self sendResult:result forProviders:nil error:error];
     }];
   } else if ([@"delete" isEqualToString:call.method]) {
-    [[self getAuth:call.arguments].currentUser deleteWithCompletion:^(NSError *_Nullable error) {
+    [[FIRAuth auth].currentUser deleteWithCompletion:^(NSError *_Nullable error) {
       [self sendResult:result forProviders:nil error:error];
     }];
   } else if ([@"sendPasswordResetEmail" isEqualToString:call.method]) {
     NSString *email = call.arguments[@"email"];
-    [[self getAuth:call.arguments]
-        sendPasswordResetWithEmail:email
-                        completion:^(NSError *error) {
-                          [self sendResult:result forUser:nil error:error];
-                        }];
+    [[FIRAuth auth] sendPasswordResetWithEmail:email
+                                    completion:^(NSError *error) {
+                                      [self sendResult:result forUser:nil error:error];
+                                    }];
   } else if ([@"signInWithEmailAndPassword" isEqualToString:call.method]) {
     NSString *email = call.arguments[@"email"];
     NSString *password = call.arguments[@"password"];
-    [[self getAuth:call.arguments]
-        signInWithEmail:email
-               password:password
-             completion:^(FIRAuthDataResult *dataResult, NSError *error) {
-               [self sendResult:result forUser:dataResult.user error:error];
-             }];
+    [[FIRAuth auth] signInWithEmail:email
+                           password:password
+                         completion:^(FIRAuthDataResult *dataResult, NSError *error) {
+                           [self sendResult:result forUser:dataResult.user error:error];
+                         }];
   } else if ([@"signOut" isEqualToString:call.method]) {
     NSError *signOutError;
-    BOOL status = [[self getAuth:call.arguments] signOut:&signOutError];
+    BOOL status = [[FIRAuth auth] signOut:&signOutError];
     if (!status) {
       NSLog(@"Error signing out: %@", signOutError);
       [self sendResult:result forUser:nil error:signOutError];
@@ -156,7 +146,7 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
       [self sendResult:result forUser:nil error:nil];
     }
   } else if ([@"getIdToken" isEqualToString:call.method]) {
-    [[self getAuth:call.arguments].currentUser
+    [[FIRAuth auth].currentUser
         getIDTokenForcingRefresh:YES
                       completion:^(NSString *_Nullable token, NSError *_Nullable error) {
                         result(error != nil ? error.flutterError : token);
@@ -166,55 +156,50 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
     NSString *password = call.arguments[@"password"];
     FIRAuthCredential *credential =
         [FIREmailAuthProvider credentialWithEmail:email password:password];
-    [[self getAuth:call.arguments].currentUser
-        linkWithCredential:credential
-                completion:^(FIRUser *user, NSError *error) {
-                  [self sendResult:result forUser:user error:error];
-                }];
+    [[FIRAuth auth].currentUser linkWithCredential:credential
+                                        completion:^(FIRUser *user, NSError *error) {
+                                          [self sendResult:result forUser:user error:error];
+                                        }];
   } else if ([@"linkWithGoogleCredential" isEqualToString:call.method]) {
     NSString *idToken = call.arguments[@"idToken"];
     NSString *accessToken = call.arguments[@"accessToken"];
     FIRAuthCredential *credential =
         [FIRGoogleAuthProvider credentialWithIDToken:idToken accessToken:accessToken];
-    [[self getAuth:call.arguments].currentUser
-        linkWithCredential:credential
-                completion:^(FIRUser *user, NSError *error) {
-                  [self sendResult:result forUser:user error:error];
-                }];
+    [[FIRAuth auth].currentUser linkWithCredential:credential
+                                        completion:^(FIRUser *user, NSError *error) {
+                                          [self sendResult:result forUser:user error:error];
+                                        }];
   } else if ([@"linkWithFacebookCredential" isEqualToString:call.method]) {
     NSString *accessToken = call.arguments[@"accessToken"];
     FIRAuthCredential *credential = [FIRFacebookAuthProvider credentialWithAccessToken:accessToken];
-    [[self getAuth:call.arguments].currentUser
-        linkWithCredential:credential
-                completion:^(FIRUser *user, NSError *error) {
-                  [self sendResult:result forUser:user error:error];
-                }];
+    [[FIRAuth auth].currentUser linkWithCredential:credential
+                                        completion:^(FIRUser *user, NSError *error) {
+                                          [self sendResult:result forUser:user error:error];
+                                        }];
   } else if ([@"linkWithTwitterCredential" isEqualToString:call.method]) {
     NSString *authToken = call.arguments[@"authToken"];
     NSString *authTokenSecret = call.arguments[@"authTokenSecret"];
     FIRAuthCredential *credential =
         [FIRTwitterAuthProvider credentialWithToken:authToken secret:authTokenSecret];
-    [[self getAuth:call.arguments].currentUser
-        linkWithCredential:credential
-                completion:^(FIRUser *user, NSError *error) {
-                  [self sendResult:result forUser:user error:error];
-                }];
+    [[FIRAuth auth].currentUser linkWithCredential:credential
+                                        completion:^(FIRUser *user, NSError *error) {
+                                          [self sendResult:result forUser:user error:error];
+                                        }];
   } else if ([@"updateEmail" isEqualToString:call.method]) {
     NSString *email = call.arguments[@"email"];
-    [[self getAuth:call.arguments].currentUser updateEmail:email
-                                                completion:^(NSError *error) {
-                                                  [self sendResult:result forUser:nil error:error];
-                                                }];
+    [[FIRAuth auth].currentUser updateEmail:email
+                                 completion:^(NSError *error) {
+                                   [self sendResult:result forUser:nil error:error];
+                                 }];
   } else if ([@"updatePassword" isEqualToString:call.method]) {
     NSString *password = call.arguments[@"password"];
-    [[self getAuth:call.arguments].currentUser
-        updatePassword:password
-            completion:^(NSError *error) {
-              [self sendResult:result forUser:nil error:error];
-            }];
+    [[FIRAuth auth].currentUser updatePassword:password
+                                    completion:^(NSError *error) {
+                                      [self sendResult:result forUser:nil error:error];
+                                    }];
+
   } else if ([@"updateProfile" isEqualToString:call.method]) {
-    FIRUserProfileChangeRequest *changeRequest =
-        [[self getAuth:call.arguments].currentUser profileChangeRequest];
+    FIRUserProfileChangeRequest *changeRequest = [[FIRAuth auth].currentUser profileChangeRequest];
     if (call.arguments[@"displayName"]) {
       changeRequest.displayName = call.arguments[@"displayName"];
     }
@@ -224,24 +209,17 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
     [changeRequest commitChangesWithCompletion:^(NSError *error) {
       [self sendResult:result forUser:nil error:error];
     }];
-  } else if ([@"updateEmail" isEqualToString:call.method]) {
-    NSString *toEmail = call.arguments[@"email"];
-    [[self getAuth:call.arguments].currentUser updateEmail:toEmail
-                                                completion:^(NSError *_Nullable error) {
-                                                  [self sendResult:result forUser:nil error:error];
-                                                }];
   } else if ([@"signInWithCustomToken" isEqualToString:call.method]) {
     NSString *token = call.arguments[@"token"];
-    [[self getAuth:call.arguments]
-        signInWithCustomToken:token
-                   completion:^(FIRAuthDataResult *dataResult, NSError *error) {
-                     [self sendResult:result forUser:dataResult.user error:error];
-                   }];
+    [[FIRAuth auth] signInWithCustomToken:token
+                               completion:^(FIRAuthDataResult *dataResult, NSError *error) {
+                                 [self sendResult:result forUser:dataResult.user error:error];
+                               }];
 
   } else if ([@"startListeningAuthState" isEqualToString:call.method]) {
     NSNumber *identifier = [NSNumber numberWithInteger:nextHandle++];
 
-    FIRAuthStateDidChangeListenerHandle listener = [[self getAuth:call.arguments]
+    FIRAuthStateDidChangeListenerHandle listener = [[FIRAuth auth]
         addAuthStateDidChangeListener:^(FIRAuth *_Nonnull auth, FIRUser *_Nullable user) {
           NSMutableDictionary *response = [[NSMutableDictionary alloc] init];
           response[@"id"] = identifier;
@@ -258,8 +236,7 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
 
     FIRAuthStateDidChangeListenerHandle listener = self.authStateChangeListeners[identifier];
     if (listener) {
-      [[self getAuth:call.arguments]
-          removeAuthStateDidChangeListener:self.authStateChangeListeners];
+      [[FIRAuth auth] removeAuthStateDidChangeListener:self.authStateChangeListeners];
       [self.authStateChangeListeners removeObjectForKey:identifier];
       result(nil);
     } else {
@@ -295,13 +272,13 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
     FIRPhoneAuthCredential *credential =
         [[FIRPhoneAuthProvider provider] credentialWithVerificationID:verificationId
                                                      verificationCode:smsCode];
-    [[self getAuth:call.arguments] signInWithCredential:credential
-                                             completion:^(FIRUser *user, NSError *error) {
-                                               [self sendResult:result forUser:user error:error];
-                                             }];
+    [[FIRAuth auth] signInWithCredential:credential
+                              completion:^(FIRUser *user, NSError *error) {
+                                [self sendResult:result forUser:user error:error];
+                              }];
   } else if ([@"setLanguageCode" isEqualToString:call.method]) {
     NSString *language = call.arguments[@"language"];
-    [[self getAuth:call.arguments] setLanguageCode:language];
+    [[FIRAuth auth] setLanguageCode:language];
     [self sendResult:result forUser:nil error:nil];
   } else {
     result(FlutterMethodNotImplemented);
diff --git a/packages/firebase_auth/lib/firebase_auth.dart b/packages/firebase_auth/lib/firebase_auth.dart
index 25c1c7899b6b..45a177331b91 100755
--- a/packages/firebase_auth/lib/firebase_auth.dart
+++ b/packages/firebase_auth/lib/firebase_auth.dart
@@ -6,7 +6,6 @@ import 'dart:async';
 
 import 'package:flutter/services.dart';
 import 'package:meta/meta.dart';
-import 'package:firebase_core/firebase_core.dart';
 
 /// Represents user data returned from an identity provider.
 
@@ -20,9 +19,7 @@ class FirebaseUserMetadata {
 }
 
 class UserInfo {
-  UserInfo._(this._data, this.app);
-
-  FirebaseApp app;
+  UserInfo._(this._data);
 
   final Map<dynamic, dynamic> _data;
 
@@ -69,12 +66,12 @@ class UserUpdateInfo {
 
 /// Represents a user.
 class FirebaseUser extends UserInfo {
-  FirebaseUser._(Map<dynamic, dynamic> data, FirebaseApp app)
+  FirebaseUser._(Map<dynamic, dynamic> data)
       : providerData = data['providerData']
-            .map<UserInfo>((dynamic item) => UserInfo._(item, app))
+            .map<UserInfo>((dynamic item) => UserInfo._(item))
             .toList(),
         _metadata = FirebaseUserMetadata._(data),
-        super._(data, app);
+        super._(data);
 
   final List<UserInfo> providerData;
   final FirebaseUserMetadata _metadata;
@@ -93,28 +90,23 @@ class FirebaseUser extends UserInfo {
   ///
   /// Completes with an error if the user is signed out.
   Future<String> getIdToken({bool refresh = false}) async {
-    return await FirebaseAuth.channel
-        .invokeMethod('getIdToken', <String, dynamic>{
+    return await FirebaseAuth.channel.invokeMethod('getIdToken', <String, bool>{
       'refresh': refresh,
-      'app': app.name,
     });
   }
 
   Future<void> sendEmailVerification() async {
-    await FirebaseAuth.channel.invokeMethod(
-        'sendEmailVerification', <String, String>{'app': app.name});
+    await FirebaseAuth.channel.invokeMethod('sendEmailVerification');
   }
 
   /// Manually refreshes the data of the current user (for example, attached providers, display name, and so on).
   Future<void> reload() async {
-    await FirebaseAuth.channel
-        .invokeMethod('reload', <String, String>{'app': app.name});
+    await FirebaseAuth.channel.invokeMethod('reload');
   }
 
   /// Deletes the user record from your Firebase project's database.
   Future<void> delete() async {
-    await FirebaseAuth.channel
-        .invokeMethod('delete', <String, String>{'app': app.name});
+    await FirebaseAuth.channel.invokeMethod('delete');
   }
 
   /// Updates the email address of the user.
@@ -122,7 +114,7 @@ class FirebaseUser extends UserInfo {
     assert(email != null);
     return await FirebaseAuth.channel.invokeMethod(
       'updateEmail',
-      <String, String>{'email': email, 'app': app.name},
+      <String, String>{'email': email},
     );
   }
 
@@ -131,18 +123,16 @@ class FirebaseUser extends UserInfo {
     assert(password != null);
     return await FirebaseAuth.channel.invokeMethod(
       'updatePassword',
-      <String, String>{'password': password, 'app': app.name},
+      <String, String>{'password': password},
     );
   }
 
   /// Updates the user profile information.
   Future<void> updateProfile(UserUpdateInfo userUpdateInfo) async {
     assert(userUpdateInfo != null);
-    final Map<String, String> data = userUpdateInfo._updateData;
-    data['app'] = app.name;
     return await FirebaseAuth.channel.invokeMethod(
       'updateProfile',
-      data,
+      userUpdateInfo._updateData,
     );
   }
 
@@ -165,15 +155,15 @@ typedef void PhoneCodeSent(String verificationId, [int forceResendingToken]);
 typedef void PhoneCodeAutoRetrievalTimeout(String verificationId);
 
 class FirebaseAuth {
-  FirebaseAuth({FirebaseApp app})
-      : app = app != null ? app : FirebaseApp.instance {
-    channel.setMethodCallHandler(_callHandler);
-  }
-
   FirebaseAuth._() {
     channel.setMethodCallHandler(_callHandler);
   }
 
+  /// Provides an instance of this class corresponding to the default app.
+  ///
+  /// TODO(jackson): Support for non-default apps.
+  static FirebaseAuth instance = FirebaseAuth._();
+
   @visibleForTesting
   static const MethodChannel channel = MethodChannel(
     'plugins.flutter.io/firebase_auth',
@@ -186,23 +176,22 @@ class FirebaseAuth {
   final Map<int, Map<String, dynamic>> _phoneAuthCallbacks =
       <int, Map<String, dynamic>>{};
 
-  FirebaseApp app;
-
   /// Receive [FirebaseUser] each time the user signIn or signOut
   Stream<FirebaseUser> get onAuthStateChanged {
     Future<int> _handle;
 
     StreamController<FirebaseUser> controller;
     controller = StreamController<FirebaseUser>.broadcast(onListen: () {
-      _handle = channel.invokeMethod('startListeningAuthState',
-          <String, String>{"app": app.name}).then<int>((dynamic v) => v);
+      _handle = channel
+          .invokeMethod('startListeningAuthState')
+          .then<int>((dynamic v) => v);
       _handle.then((int handle) {
         _authStateChangedControllers[handle] = controller;
       });
     }, onCancel: () {
       _handle.then((int handle) async {
-        await channel.invokeMethod("stopListeningAuthState",
-            <String, dynamic>{"id": handle, "app": app.name});
+        await channel.invokeMethod(
+            "stopListeningAuthState", <String, int>{"id": handle});
         _authStateChangedControllers.remove(handle);
       });
     });
@@ -220,9 +209,9 @@ class FirebaseAuth {
   /// FIRAuthErrorCodeOperationNotAllowed - Indicates that anonymous accounts are not enabled. Enable them in the Auth section of the Firebase console.
   /// See FIRAuthErrors for a list of error codes that are common to all API methods.
   Future<FirebaseUser> signInAnonymously() async {
-    final Map<dynamic, dynamic> data = await channel
-        .invokeMethod('signInAnonymously', <String, String>{"app": app.name});
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final Map<dynamic, dynamic> data =
+        await channel.invokeMethod('signInAnonymously');
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -234,9 +223,12 @@ class FirebaseAuth {
     assert(password != null);
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'createUserWithEmailAndPassword',
-      <String, String>{'email': email, 'password': password, 'app': app.name},
+      <String, String>{
+        'email': email,
+        'password': password,
+      },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -246,7 +238,9 @@ class FirebaseAuth {
     assert(email != null);
     final List<dynamic> providers = await channel.invokeMethod(
       'fetchProvidersForEmail',
-      <String, String>{'email': email, 'app': app.name},
+      <String, String>{
+        'email': email,
+      },
     );
     return providers?.cast<String>();
   }
@@ -257,7 +251,9 @@ class FirebaseAuth {
     assert(email != null);
     return await channel.invokeMethod(
       'sendPasswordResetEmail',
-      <String, String>{'email': email, 'app': app.name},
+      <String, String>{
+        'email': email,
+      },
     );
   }
 
@@ -269,19 +265,23 @@ class FirebaseAuth {
     assert(password != null);
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'signInWithEmailAndPassword',
-      <String, String>{'email': email, 'password': password, 'app': app.name},
+      <String, String>{
+        'email': email,
+        'password': password,
+      },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
   Future<FirebaseUser> signInWithFacebook(
       {@required String accessToken}) async {
     assert(accessToken != null);
-    final Map<dynamic, dynamic> data = await channel.invokeMethod(
-        'signInWithFacebook',
-        <String, String>{'accessToken': accessToken, 'app': app.name});
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final Map<dynamic, dynamic> data =
+        await channel.invokeMethod('signInWithFacebook', <String, String>{
+      'accessToken': accessToken,
+    });
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -294,13 +294,12 @@ class FirebaseAuth {
   }) async {
     assert(authToken != null);
     assert(authTokenSecret != null);
-    final Map<dynamic, dynamic> data = await channel.invokeMethod(
-        'signInWithTwitter', <String, String>{
+    final Map<dynamic, dynamic> data =
+        await channel.invokeMethod('signInWithTwitter', <String, String>{
       'authToken': authToken,
       'authTokenSecret': authTokenSecret,
-      'app': app.name
     });
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -315,10 +314,9 @@ class FirebaseAuth {
       <String, String>{
         'idToken': idToken,
         'accessToken': accessToken,
-        'app': app.name
       },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -331,10 +329,9 @@ class FirebaseAuth {
       <String, String>{
         'verificationId': verificationId,
         'smsCode': smsCode,
-        'app': app.name
       },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -361,7 +358,6 @@ class FirebaseAuth {
       'phoneNumber': phoneNumber,
       'timeout': timeout.inMilliseconds,
       'forceResendingToken': forceResendingToken,
-      'app': app.name
     };
 
     await channel.invokeMethod('verifyPhoneNumber', params);
@@ -371,23 +367,23 @@ class FirebaseAuth {
     assert(token != null);
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'signInWithCustomToken',
-      <String, String>{'token': token, 'app': app.name},
+      <String, String>{
+        'token': token,
+      },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
   Future<void> signOut() async {
-    return await channel
-        .invokeMethod("signOut", <String, String>{'app': app.name});
+    return await channel.invokeMethod("signOut");
   }
 
   /// Asynchronously gets current user, or `null` if there is none.
   Future<FirebaseUser> currentUser() async {
-    final Map<dynamic, dynamic> data = await channel
-        .invokeMethod("currentUser", <String, String>{'app': app.name});
-    final FirebaseUser currentUser =
-        data == null ? null : FirebaseUser._(data, app);
+    final Map<dynamic, dynamic> data =
+        await channel.invokeMethod("currentUser");
+    final FirebaseUser currentUser = data == null ? null : FirebaseUser._(data);
     return currentUser;
   }
 
@@ -405,9 +401,12 @@ class FirebaseAuth {
     assert(password != null);
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'linkWithEmailAndPassword',
-      <String, String>{'email': email, 'password': password, 'app': app.name},
+      <String, String>{
+        'email': email,
+        'password': password,
+      },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -430,10 +429,9 @@ class FirebaseAuth {
       <String, String>{
         'idToken': idToken,
         'accessToken': accessToken,
-        'app': app.name
       },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -443,9 +441,11 @@ class FirebaseAuth {
     assert(accessToken != null);
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'linkWithFacebookCredential',
-      <String, String>{'accessToken': accessToken, 'app': app.name},
+      <String, String>{
+        'accessToken': accessToken,
+      },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -456,12 +456,11 @@ class FirebaseAuth {
     final Map<dynamic, dynamic> data = await channel.invokeMethod(
       'linkWithTwitterCredential',
       <String, String>{
-        'app': app.name,
         'authToken': authToken,
         'authTokenSecret': authTokenSecret,
       },
     );
-    final FirebaseUser currentUser = FirebaseUser._(data, app);
+    final FirebaseUser currentUser = FirebaseUser._(data);
     return currentUser;
   }
 
@@ -472,7 +471,6 @@ class FirebaseAuth {
     assert(language != null);
     await FirebaseAuth.channel.invokeMethod('setLanguageCode', <String, String>{
       'language': language,
-      'app': app.name,
     });
   }
 
@@ -522,8 +520,7 @@ class FirebaseAuth {
     final Map<dynamic, dynamic> data = call.arguments["user"];
     final int id = call.arguments["id"];
 
-    final FirebaseUser currentUser =
-        data != null ? FirebaseUser._(data, app) : null;
+    final FirebaseUser currentUser = data != null ? FirebaseUser._(data) : null;
     _authStateChangedControllers[id].add(currentUser);
   }
 }
diff --git a/packages/firebase_auth/pubspec.yaml b/packages/firebase_auth/pubspec.yaml
index 3f5ff50a108f..528a98f9cbd0 100755
--- a/packages/firebase_auth/pubspec.yaml
+++ b/packages/firebase_auth/pubspec.yaml
@@ -14,8 +14,6 @@ flutter:
 
 dependencies:
   meta: ^1.0.4
-  firebase_core: ^0.2.5+1
-
   flutter:
     sdk: flutter
 
@@ -24,6 +22,7 @@ dev_dependencies:
   test: ^1.3.0
   flutter_test:
     sdk: flutter
+  firebase_core: ^0.2.5+1
 
 environment:
   sdk: ">=2.0.0-dev.28.0 <3.0.0"
diff --git a/packages/firebase_auth/test/firebase_auth_test.dart b/packages/firebase_auth/test/firebase_auth_test.dart
index 7b3b97c7d31f..d5f0e3146ee7 100755
--- a/packages/firebase_auth/test/firebase_auth_test.dart
+++ b/packages/firebase_auth/test/firebase_auth_test.dart
@@ -5,7 +5,6 @@
 import 'dart:async';
 
 import 'package:firebase_auth/firebase_auth.dart';
-import 'package:firebase_core/firebase_core.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
@@ -27,9 +26,7 @@ const String kMockLanguage = 'en';
 
 void main() {
   group('$FirebaseAuth', () {
-    final String appName = 'testApp';
-    final FirebaseApp app = FirebaseApp(name: appName);
-    final FirebaseAuth auth = FirebaseAuth(app: app);
+    final FirebaseAuth auth = FirebaseAuth.instance;
     final List<MethodCall> log = <MethodCall>[];
 
     int mockHandleId = 0;
@@ -82,8 +79,7 @@ void main() {
       expect(
         log,
         <Matcher>[
-          isMethodCall('currentUser',
-              arguments: <String, String>{'app': auth.app.name}),
+          isMethodCall('currentUser', arguments: null),
         ],
       );
     });
@@ -96,18 +92,14 @@ void main() {
       expect(
         log,
         <Matcher>[
-          isMethodCall('signInAnonymously',
-              arguments: <String, String>{'app': auth.app.name}),
+          isMethodCall('signInAnonymously', arguments: null),
           isMethodCall(
             'getIdToken',
-            arguments: <String, dynamic>{
-              'refresh': false,
-              'app': auth.app.name
-            },
+            arguments: <String, bool>{'refresh': false},
           ),
           isMethodCall(
             'getIdToken',
-            arguments: <String, dynamic>{'refresh': true, 'app': auth.app.name},
+            arguments: <String, bool>{'refresh': true},
           ),
         ],
       );
@@ -127,7 +119,6 @@ void main() {
             arguments: <String, String>{
               'email': kMockEmail,
               'password': kMockPassword,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -144,10 +135,7 @@ void main() {
         <Matcher>[
           isMethodCall(
             'fetchProvidersForEmail',
-            arguments: <String, String>{
-              'email': kMockEmail,
-              'app': auth.app.name
-            },
+            arguments: <String, String>{'email': kMockEmail},
           ),
         ],
       );
@@ -167,7 +155,6 @@ void main() {
             arguments: <String, String>{
               'email': kMockEmail,
               'password': kMockPassword,
-              'app': auth.app.name
             },
           ),
         ],
@@ -188,7 +175,6 @@ void main() {
             arguments: <String, String>{
               'idToken': kMockIdToken,
               'accessToken': kMockAccessToken,
-              'app': auth.app.name
             },
           ),
         ],
@@ -202,7 +188,6 @@ void main() {
         isMethodCall('signInWithPhoneNumber', arguments: <String, dynamic>{
           'verificationId': kMockVerificationId,
           'smsCode': kMockSmsCode,
-          'app': auth.app.name,
         })
       ]);
     });
@@ -221,7 +206,6 @@ void main() {
           'phoneNumber': kMockPhoneNumber,
           'timeout': 5000,
           'forceResendingToken': null,
-          'app': auth.app.name,
         })
       ]);
     });
@@ -240,7 +224,6 @@ void main() {
             arguments: <String, String>{
               'idToken': kMockIdToken,
               'accessToken': kMockAccessToken,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -259,7 +242,6 @@ void main() {
             'linkWithFacebookCredential',
             arguments: <String, String>{
               'accessToken': kMockAccessToken,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -280,7 +262,6 @@ void main() {
             arguments: <String, String>{
               'authToken': kMockAuthToken,
               'authTokenSecret': kMockAuthTokenSecret,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -299,7 +280,6 @@ void main() {
             'signInWithFacebook',
             arguments: <String, String>{
               'accessToken': kMockAccessToken,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -320,7 +300,6 @@ void main() {
             arguments: <String, String>{
               'email': kMockEmail,
               'password': kMockPassword,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -336,11 +315,11 @@ void main() {
         <Matcher>[
           isMethodCall(
             'currentUser',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
           isMethodCall(
             'sendEmailVerification',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
         ],
       );
@@ -355,11 +334,11 @@ void main() {
         <Matcher>[
           isMethodCall(
             'currentUser',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
           isMethodCall(
             'reload',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
         ],
       );
@@ -374,11 +353,11 @@ void main() {
         <Matcher>[
           isMethodCall(
             'currentUser',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
           isMethodCall(
             'delete',
-            arguments: <String, String>{'app': auth.app.name},
+            arguments: null,
           ),
         ],
       );
@@ -395,7 +374,6 @@ void main() {
             'sendPasswordResetEmail',
             arguments: <String, String>{
               'email': kMockEmail,
-              'app': auth.app.name
             },
           ),
         ],
@@ -408,13 +386,12 @@ void main() {
       expect(log, <Matcher>[
         isMethodCall(
           'currentUser',
-          arguments: <String, String>{'app': auth.app.name},
+          arguments: null,
         ),
         isMethodCall(
           'updateEmail',
           arguments: <String, String>{
             'email': kMockEmail,
-            'app': auth.app.name,
           },
         ),
       ]);
@@ -426,13 +403,12 @@ void main() {
       expect(log, <Matcher>[
         isMethodCall(
           'currentUser',
-          arguments: <String, String>{'app': auth.app.name},
+          arguments: null,
         ),
         isMethodCall(
           'updatePassword',
           arguments: <String, String>{
             'password': kMockPassword,
-            'app': auth.app.name,
           },
         ),
       ]);
@@ -448,14 +424,13 @@ void main() {
       expect(log, <Matcher>[
         isMethodCall(
           'currentUser',
-          arguments: <String, String>{'app': auth.app.name},
+          arguments: null,
         ),
         isMethodCall(
           'updateProfile',
           arguments: <String, String>{
             'photoUrl': kMockPhotoUrl,
             'displayName': kMockDisplayName,
-            'app': auth.app.name,
           },
         ),
       ]);
@@ -470,7 +445,6 @@ void main() {
         <Matcher>[
           isMethodCall('signInWithCustomToken', arguments: <String, String>{
             'token': kMockCustomToken,
-            'app': auth.app.name,
           })
         ],
       );
@@ -485,7 +459,7 @@ void main() {
           FirebaseAuth.channel.codec.encodeMethodCall(
             MethodCall(
               'onAuthStateChanged',
-              <String, dynamic>{'id': 42, 'user': user, 'app': auth.app.name},
+              <String, dynamic>{'id': 42, 'user': user},
             ),
           ),
           (_) {},
@@ -515,14 +489,11 @@ void main() {
       expect(
         log,
         <Matcher>[
-          isMethodCall('startListeningAuthState', arguments: <String, String>{
-            'app': auth.app.name,
-          }),
+          isMethodCall('startListeningAuthState', arguments: null),
           isMethodCall(
             'stopListeningAuthState',
             arguments: <String, dynamic>{
               'id': 42,
-              'app': auth.app.name,
             },
           ),
         ],
@@ -539,7 +510,6 @@ void main() {
             'setLanguageCode',
             arguments: <String, String>{
               'language': kMockLanguage,
-              'app': auth.app.name,
             },
           ),
         ],