diff --git a/functions_call_flutter/lib/functions_call_flutter.dart b/functions_call_flutter/lib/functions_call_flutter.dart
index 0338f94..7eba210 100644
--- a/functions_call_flutter/lib/functions_call_flutter.dart
+++ b/functions_call_flutter/lib/functions_call_flutter.dart
@@ -1,5 +1,7 @@
 library;
 
+export 'package:tekartik_firebase_functions/firebase_functions.dart'
+    show regionBelgium, regionUsCentral1, regionFrankfurt;
 export 'src/functions_call.dart'
     show
         FirebaseFunctionsCallService,
diff --git a/functions_call_flutter/lib/src/functions_call.dart b/functions_call_flutter/lib/src/functions_call.dart
index 54173cd..0f5aaa0 100644
--- a/functions_call_flutter/lib/src/functions_call.dart
+++ b/functions_call_flutter/lib/src/functions_call.dart
@@ -14,6 +14,10 @@ class FirebaseFunctionsCallableOptions {
 
   /// Sets whether or not to use limited-use App Check tokens when invoking the associated function.
   bool limitedUseAppCheckToken;
+
+  @override
+  String toString() =>
+      'FirebaseFunctionsCallableOptions(timeout: $timeout${limitedUseAppCheckToken == true ? ', limitedUseAppCheckToken: $limitedUseAppCheckToken' : ''})';
 }
 
 /// Firebase functions call
@@ -72,15 +76,16 @@ mixin FirebaseFunctionsCallDefaultMixin implements FirebaseFunctionsCall {
 /// Firebase functions call service
 abstract class FirebaseFunctionsCallService {
   /// Get the firebase functions call instance
-  FirebaseFunctionsCall functionsCall(App app);
+  FirebaseFunctionsCall functionsCall(App app, {required String region});
 }
 
 /// Firebase functions call service default mixin
 mixin FirebaseFunctionsCallServiceDefaultMixin
     implements FirebaseFunctionsCallService {
   @override
-  FirebaseFunctionsCall functionsCall(App app) {
-    throw UnimplementedError('FirebaseFunctionsCallService.functionsCall');
+  FirebaseFunctionsCall functionsCall(App app, {required String region}) {
+    throw UnimplementedError(
+        'FirebaseFunctionsCallService.functionsCall(${app.name}, $region)');
   }
 }
 
diff --git a/functions_call_flutter/lib/src/functions_call_flutter.dart b/functions_call_flutter/lib/src/functions_call_flutter.dart
index cd5caae..c01641f 100644
--- a/functions_call_flutter/lib/src/functions_call_flutter.dart
+++ b/functions_call_flutter/lib/src/functions_call_flutter.dart
@@ -1,4 +1,5 @@
 import 'package:cloud_functions/cloud_functions.dart' as native;
+import 'package:tekartik_common_utils/common_utils_import.dart';
 import 'package:tekartik_firebase/firebase.dart';
 // ignore: implementation_imports
 import 'package:tekartik_firebase_flutter/src/firebase_flutter.dart'
@@ -16,22 +17,32 @@ FirebaseFunctionsCallService get firebaseFunctionsCallServiceFlutter =>
 
 /// Firebase functions call service flutter
 class FirebaseFunctionsCallServiceFlutter
-    with FirebaseProductServiceMixin<FirebaseFunctionsCallFlutter>
     implements FirebaseFunctionsCallService {
+  /// Most implementation need a single instance, keep it in memory!
+  final _instances = <String, FirebaseFunctionsCallFlutter>{};
+
+  FirebaseFunctionsCallFlutter _getInstance(App app, String region,
+      FirebaseFunctionsCallFlutter Function() createIfNotFound) {
+    var key = '${app.name}_$region';
+    var instance = _instances[key];
+    if (instance == null) {
+      var newInstance = instance = createIfNotFound();
+      _instances[key] = newInstance;
+    }
+    return instance;
+  }
+
   @override
-  FirebaseFunctionsCallFlutter functionsCall(App app) {
-    return getInstance(app, () {
+  FirebaseFunctionsCallFlutter functionsCall(App app,
+      {required String region}) {
+    return _getInstance(app, region, () {
       assert(app is FirebaseAppFlutter, 'invalid firebase app type');
       var appFlutter = app as FirebaseAppFlutter;
-      if (appFlutter.isDefault!) {
-        return FirebaseFunctionsCallFlutter(
-            this, native.FirebaseFunctions.instance);
-      } else {
-        return FirebaseFunctionsCallFlutter(
-            this,
-            native.FirebaseFunctions.instanceFor(
-                app: appFlutter.nativeInstance!));
-      }
+
+      return FirebaseFunctionsCallFlutter(
+          this,
+          native.FirebaseFunctions.instanceFor(
+              app: appFlutter.nativeInstance!, region: region));
     });
   }
 }
diff --git a/functions_call_flutter/pubspec.yaml b/functions_call_flutter/pubspec.yaml
index 434fcd9..c0caa2e 100644
--- a/functions_call_flutter/pubspec.yaml
+++ b/functions_call_flutter/pubspec.yaml
@@ -26,6 +26,15 @@ dependencies:
       url: https://github.com/tekartik/firebase.dart
       ref: dart3a
       path: firebase
+  tekartik_common_utils:
+    git:
+      url: https://github.com/tekartik/common_utils.dart
+      ref: dart3a
+  tekartik_firebase_functions:
+    git:
+      url: https://github.com/tekartik/firebase_functions.dart
+      ref: dart3a
+      path: firebase_functions
 dev_dependencies:
   flutter_test:
     sdk: flutter