diff --git a/android/gradle.properties b/android/gradle.properties
index 38c8d4544..7199c1559 100644
--- a/android/gradle.properties
+++ b/android/gradle.properties
@@ -2,3 +2,4 @@ org.gradle.jvmargs=-Xmx1536M
 android.enableR8=true
 android.useAndroidX=true
 android.enableJetifier=true
+org.gradle.java.home=C:\\Program Files\\Java\\jdk1.8.0_181
diff --git a/cw_haven/ios/Classes/haven_api.cpp b/cw_haven/ios/Classes/haven_api.cpp
index c1013bf87..65957c277 100644
--- a/cw_haven/ios/Classes/haven_api.cpp
+++ b/cw_haven/ios/Classes/haven_api.cpp
@@ -927,6 +927,25 @@ extern "C"
         return static_cast<int32_t>(rates.size());
     }
 
+    uint64_t estimate_transaction_fee(int outputs, uint8_t priority_raw)
+    {
+        // estimateTransactionFee only cares about the number of outputs
+        std::vector<std::pair<std::string, uint64_t>> destinations;
+        for (int i = 0; i < outputs; i++) {
+            destinations.push_back({"", 0});
+        }
+        auto priority = static_cast<Monero::PendingTransaction::Priority>(priority_raw);
+
+        try {
+           return m_wallet->estimateTransactionFee(destinations, priority);
+        }
+        catch (...) {
+            // estimateTransactionFee can throw an exception if there is a problem with the
+            // network request. We must catch it here because exceptions don't propagate to Dart.
+            return 0;
+        }
+    }
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/cw_haven/lib/api/signatures.dart b/cw_haven/lib/api/signatures.dart
index 9dd1c8dac..5c4c80d7a 100644
--- a/cw_haven/lib/api/signatures.dart
+++ b/cw_haven/lib/api/signatures.dart
@@ -137,4 +137,8 @@ typedef get_rate = Pointer<Int64> Function();
 
 typedef size_of_rate = Int32 Function();
 
-typedef update_rate = Void Function();
\ No newline at end of file
+typedef update_rate = Void Function();
+
+typedef estimate_transaction_fee = Int64 Function(
+    Int32 outputs,
+    Int8 priorityRaw);
\ No newline at end of file
diff --git a/cw_haven/lib/api/types.dart b/cw_haven/lib/api/types.dart
index 878297501..c789f0599 100644
--- a/cw_haven/lib/api/types.dart
+++ b/cw_haven/lib/api/types.dart
@@ -135,4 +135,6 @@ typedef GetRate = Pointer<Int64> Function();
 
 typedef SizeOfRate = int Function();
 
-typedef UpdateRate = void Function();
\ No newline at end of file
+typedef UpdateRate = void Function();
+
+typedef EstimateTransactionFee = int Function(int, int);
\ No newline at end of file
diff --git a/cw_haven/lib/api/wallet.dart b/cw_haven/lib/api/wallet.dart
index 3370fd3e0..9dbefce8e 100644
--- a/cw_haven/lib/api/wallet.dart
+++ b/cw_haven/lib/api/wallet.dart
@@ -8,7 +8,6 @@ import 'package:cw_haven/api/types.dart';
 import 'package:cw_haven/api/haven_api.dart';
 import 'package:cw_haven/api/exceptions/setup_wallet_exception.dart';
 import 'package:flutter/foundation.dart';
-import 'package:flutter/services.dart';
 
 int _boolToInt(bool value) => value ? 1 : 0;
 
@@ -116,6 +115,10 @@ final rescanBlockchainAsyncNative = havenApi
     .lookup<NativeFunction<rescan_blockchain>>('rescan_blockchain')
     .asFunction<RescanBlockchainAsync>();
 
+final estimateTransactionFeeNative = havenApi
+    .lookup<NativeFunction<estimate_transaction_fee>>('estimate_transaction_fee')
+    .asFunction<EstimateTransactionFee>();
+
 int getSyncingHeight() => getSyncingHeightNative();
 
 bool isNeededToRefresh() => isNeededToRefreshNative() != 0;
@@ -346,3 +349,18 @@ Future<bool> isConnected() => compute(_isConnected, 0);
 Future<int> getNodeHeight() => compute(_getNodeHeight, 0);
 
 void rescanBlockchainAsync() => rescanBlockchainAsyncNative();
+
+int estimateTransactionFeeSync(int outputs, int priorityRaw) {
+  return estimateTransactionFeeNative(outputs, priorityRaw);
+}
+
+int _estimateTransactionFee(Map args) {
+  final priorityRaw = args['priorityRaw'] as int;
+  final outputsCount = args['outputsCount'] as int;
+
+  return estimateTransactionFeeSync(outputsCount, priorityRaw);
+}
+
+Future<int> estimateTransactionFee({int priorityRaw, int outputsCount}) {
+  return compute(_estimateTransactionFee, {'priorityRaw': priorityRaw, 'outputsCount': outputsCount});
+}
\ No newline at end of file
diff --git a/cw_haven/lib/haven_fee_estimate.dart b/cw_haven/lib/haven_fee_estimate.dart
new file mode 100644
index 000000000..826690887
--- /dev/null
+++ b/cw_haven/lib/haven_fee_estimate.dart
@@ -0,0 +1,38 @@
+import 'package:mobx/mobx.dart';
+import 'package:cw_core/fee_estimate.dart';
+import 'package:cw_core/transaction_priority.dart';
+import 'package:cw_haven/api/wallet.dart' as haven_wallet;
+
+part 'haven_fee_estimate.g.dart';
+
+class HavenFeeEstimate = _HavenFeeEstimate with _$HavenFeeEstimate;
+
+abstract class _HavenFeeEstimate extends FeeEstimate with Store {
+  _HavenFeeEstimate()
+      : _estimatedFee = new ObservableMap<String, int>();
+
+  @observable
+  ObservableMap<String, int> _estimatedFee;
+
+  @override
+  void update({TransactionPriority priority, int outputsCount}) {
+    Future(() async {
+      final fee = await haven_wallet.estimateTransactionFee(priorityRaw: priority.raw, outputsCount: outputsCount);
+      set(priority: priority, fee: fee, outputsCount: outputsCount);
+    });
+  }
+
+  @override
+  int get({TransactionPriority priority, int amount, int outputsCount}) {
+    return _estimatedFee[_key(priority, outputsCount)] ?? 0;
+  }
+
+  @override
+  void set({TransactionPriority priority, int outputsCount, int fee}) {
+    _estimatedFee[_key(priority, outputsCount)] = fee;
+  }
+
+  String _key(TransactionPriority priority, int outputsCount) {
+    return "$priority:$outputsCount";
+  }
+}
\ No newline at end of file
diff --git a/cw_haven/lib/haven_wallet.dart b/cw_haven/lib/haven_wallet.dart
index c107d2f52..50fb2c1bf 100644
--- a/cw_haven/lib/haven_wallet.dart
+++ b/cw_haven/lib/haven_wallet.dart
@@ -1,6 +1,5 @@
 import 'dart:async';
 import 'package:cw_core/crypto_currency.dart';
-import 'package:cw_core/transaction_priority.dart';
 import 'package:cw_haven/haven_transaction_creation_credentials.dart';
 import 'package:cw_core/monero_amount_format.dart';
 import 'package:cw_haven/haven_transaction_creation_exception.dart';
@@ -26,8 +25,8 @@ import 'package:cw_core/wallet_base.dart';
 import 'package:cw_core/sync_status.dart';
 import 'package:cw_core/wallet_info.dart';
 import 'package:cw_core/node.dart';
-import 'package:cw_core/monero_transaction_priority.dart';
 import 'package:cw_haven/haven_balance.dart';
+import 'package:cw_haven/haven_fee_estimate.dart';
 
 part 'haven_wallet.g.dart';
 
@@ -49,10 +48,14 @@ abstract class HavenWalletBase extends WalletBase<MoneroBalance,
       balance.addAll(getHavenBalance(accountIndex: account.id));
       walletAddresses.updateSubaddressList(accountIndex: account.id);
     });
+    feeEstimate = HavenFeeEstimate();
   }
 
   static const int _autoSaveInterval = 30;
 
+  @override
+  HavenFeeEstimate feeEstimate;
+
   @override
   HavenWalletAddresses walletAddresses;
 
@@ -211,28 +214,6 @@ abstract class HavenWalletBase extends WalletBase<MoneroBalance,
     return PendingHavenTransaction(pendingTransactionDescription, assetType);
   }
 
-  @override
-  int calculateEstimatedFee(TransactionPriority priority, int amount) {
-    // FIXME: hardcoded value;
-
-    if (priority is MoneroTransactionPriority) {
-      switch (priority) {
-        case MoneroTransactionPriority.slow:
-          return 24590000;
-        case MoneroTransactionPriority.regular:
-          return 123050000;
-        case MoneroTransactionPriority.medium:
-          return 245029999;
-        case MoneroTransactionPriority.fast:
-          return 614530000;
-        case MoneroTransactionPriority.fastest:
-          return 26021600000;
-      }
-    }
-
-    return 0;
-  }
-
   @override
   Future<void> save() async {
     await walletAddresses.updateAddressesInBox();
diff --git a/lib/reactions/on_current_wallet_change.dart b/lib/reactions/on_current_wallet_change.dart
index ab1838d58..5910f90cd 100644
--- a/lib/reactions/on_current_wallet_change.dart
+++ b/lib/reactions/on_current_wallet_change.dart
@@ -15,7 +15,6 @@ import 'package:cake_wallet/store/settings_store.dart';
 import 'package:cake_wallet/core/fiat_conversion_service.dart';
 import 'package:cw_core/wallet_base.dart';
 import 'package:cw_core/wallet_type.dart';
-import 'package:cake_wallet/store/yat/yat_store.dart';
 
 ReactionDisposer _onCurrentWalletChangeReaction;
 ReactionDisposer _onCurrentWalletChangeFiatRateUpdateReaction;
@@ -53,7 +52,7 @@ void startCurrentWalletChangeReaction(AppStore appStore,
       wallet) async {
     try {
       final node = settingsStore.getCurrentNode(wallet.type);
-      startWalletSyncStatusChangeReaction(wallet, fiatConversionStore);
+      startWalletSyncStatusChangeReaction(wallet, fiatConversionStore, settingsStore);
       startCheckConnectionReaction(wallet, settingsStore);
       await getIt
           .get<SharedPreferences>()
diff --git a/lib/reactions/on_wallet_sync_status_change.dart b/lib/reactions/on_wallet_sync_status_change.dart
index 60e401e82..122c332bc 100644
--- a/lib/reactions/on_wallet_sync_status_change.dart
+++ b/lib/reactions/on_wallet_sync_status_change.dart
@@ -2,17 +2,14 @@ import 'package:cake_wallet/di.dart';
 import 'package:cake_wallet/entities/update_haven_rate.dart';
 import 'package:cake_wallet/entities/wake_lock.dart';
 import 'package:cake_wallet/store/settings_store.dart';
-import 'package:cw_core/transaction_priority.dart';
 import 'package:cake_wallet/store/dashboard/fiat_conversion_store.dart';
 import 'package:cw_core/wallet_type.dart';
-import 'package:cw_monero/monero_transaction_priority.dart';
 import 'package:mobx/mobx.dart';
 import 'package:cw_core/transaction_history.dart';
 import 'package:cw_core/wallet_base.dart';
 import 'package:cw_core/balance.dart';
 import 'package:cw_core/transaction_info.dart';
 import 'package:cw_core/sync_status.dart';
-import 'package:flutter/services.dart';
 
 ReactionDisposer _onWalletSyncStatusChangeReaction;
 
diff --git a/lib/src/screens/send/widgets/send_card.dart b/lib/src/screens/send/widgets/send_card.dart
index 73b83c213..e4557b360 100644
--- a/lib/src/screens/send/widgets/send_card.dart
+++ b/lib/src/screens/send/widgets/send_card.dart
@@ -265,7 +265,6 @@ class SendCardState extends State<SendCard>
                                                 child: InkWell(
                                                     onTap: () {
                                                       output.setSendAll();
-                                                      cryptoAmountController.text = sendViewModel.balance;
                                                     },
                                                     child: Container(
                                                       decoration: BoxDecoration(
@@ -557,10 +556,13 @@ class SendCardState extends State<SendCard>
 
     reaction((_) => output.fiatAmount, (String amount) {
       if (amount != fiatAmountController.text) {
-        fiatAmountController.text = amount;
-        // final doubleAmount = double.tryParse(amount) ?? 0;
-        // final doubleFee = double.tryParse(sendViewModel.estimatedFiatFee(sendViewModel.balance)) ?? 0;
-        // fiatAmountController.text = doubleAmount - doubleFee > 0 ? "${doubleAmount - doubleFee}" : "0.00";
+        if (sendViewModel.outputs[0].sendAll) {
+          final doubleAmount = double.tryParse(amount) ?? 0;
+          final doubleFee = sendViewModel.estimatedFee;
+          fiatAmountController.text = doubleAmount - doubleFee > 0 ? "${doubleAmount - doubleFee}" : "0.00";
+        } else {
+          fiatAmountController.text = amount;
+        }
       }
     });
 
diff --git a/lib/view_model/send/output.dart b/lib/view_model/send/output.dart
index 9d1eb6dc3..195d77813 100644
--- a/lib/view_model/send/output.dart
+++ b/lib/view_model/send/output.dart
@@ -193,7 +193,7 @@ abstract class OutputBase with Store {
 
   int _estimateAmountAll() {
     final fee = _wallet.feeEstimate.get(priority: _settingsStore.priority[_wallet.type], outputsCount: 1);
-    return max(0, _wallet.balance.available - fee);
+    return max(0, _wallet.balance[cryptoCurrencyHandler()].available - fee);
   }
 
   Future<void> fetchParsedAddress(BuildContext context) async {
diff --git a/lib/view_model/send/send_view_model.dart b/lib/view_model/send/send_view_model.dart
index f1a59557f..c030b918e 100644
--- a/lib/view_model/send/send_view_model.dart
+++ b/lib/view_model/send/send_view_model.dart
@@ -1,5 +1,3 @@
-import 'package:cake_wallet/core/amount_converter.dart';
-import 'package:cake_wallet/entities/balance_display_mode.dart';
 import 'package:cake_wallet/entities/format_amount.dart';
 import 'package:cake_wallet/entities/transaction_description.dart';
 import 'package:cake_wallet/view_model/dashboard/balance_view_model.dart';
@@ -58,6 +56,8 @@ abstract class SendViewModelBase with Store {
     _settingsStore.priority.observe((change) async {
       _wallet.feeEstimate.update(priority: change.newValue, outputsCount: outputs.length);
     });
+
+    estimateFee();
   }
 
   @observable
@@ -166,16 +166,6 @@ abstract class SendViewModelBase with Store {
 
   bool get hasCurrecyChanger => walletType == WalletType.haven;
 
-  int estimatedFee(String amount) {
-    return _wallet.calculateEstimatedFee(_settingsStore.priority[_wallet.type], AmountConverter.amountStringToInt(
-        selectedCryptoCurrency, amount));
-  }
-
-  String estimatedFiatFee(String amount) {
-    return _calculateFiatAmount(AmountConverter.amountIntToString(
-        selectedCryptoCurrency, estimatedFee(amount)));
-  }
-
   final WalletBase _wallet;
   final SettingsStore _settingsStore;
   final SendTemplateViewModel sendTemplateViewModel;
@@ -286,7 +276,11 @@ abstract class SendViewModelBase with Store {
         totalFormattedCryptoAmount += output.formattedCryptoAmount;
       }
 
-      final fee = _wallet.feeEstimate.get(priority: _settingsStore.priority[_wallet.type], amount: totalFormattedCryptoAmount, outputsCount: outputs.length);
+      final fee = _wallet.feeEstimate.get(
+        priority: _settingsStore.priority[_wallet.type],
+        amount: totalFormattedCryptoAmount,
+        outputsCount: outputs.length,
+      );
 
       return formatAmountToDouble(type: _wallet.type, amount: fee);
     } catch (e) {