diff --git a/src/js/controllers/amount.js b/src/js/controllers/amount.js
index adbb21a61..2d0a5aa28 100644
--- a/src/js/controllers/amount.js
+++ b/src/js/controllers/amount.js
@@ -9,6 +9,8 @@ angular.module('copayApp.controllers').controller('amountController', function($
   var satToBtc;
   var SMALL_FONT_SIZE_LIMIT = 10;
   var LENGTH_EXPRESSION_LIMIT = 19;
+  var LENGTH_BEFORE_COMMA_EXPRESSION_LIMIT = 8;
+  var LENGTH_AFTER_COMMA_EXPRESSION_LIMIT = 8;
   var isNW = platformInfo.isNW;
 
   var unitIndex = 0;
@@ -253,13 +255,8 @@ angular.module('copayApp.controllers').controller('amountController', function($
   };
 
   $scope.changeUnit = function() {
-    $scope.amountModel.amount = '0';
 
-    if ($scope.alternativeAmount == 0) {
-      $scope.alternativeAmount = null;
-    } else {
-        $scope.amountModel.amount = parseFloat($scope.alternativeAmount.replace(/[^0-9-.]/g, ''));
-    }
+    $scope.amountModel.amount = '0';
 
     if (fixedUnit) return;
 
@@ -269,7 +266,6 @@ angular.module('copayApp.controllers').controller('amountController', function($
     }
 
     if (availableUnits[unitIndex].isFiat) {
-      $scope.amountModel.amount = parseFloat($scope.amountModel.amount).toFixed(2);
       altUnitIndex = altUnitIndex == 0 && availableUnits.length > 2 ? 1 : 0;
     } else {
       altUnitIndex = lodash.findIndex(availableUnits, {
@@ -304,6 +300,12 @@ angular.module('copayApp.controllers').controller('amountController', function($
   };
 
   $scope.pushDigit = function(digit) {
+    if ($scope.amountModel.amount && digit != '.') {
+      var amountSplitByComma = $scope.amountModel.amount.split('.');
+      if (amountSplitByComma.length > 1 && amountSplitByComma[1].length >= LENGTH_AFTER_COMMA_EXPRESSION_LIMIT) return;
+      if (amountSplitByComma.length == 1 && amountSplitByComma[0].length >= LENGTH_BEFORE_COMMA_EXPRESSION_LIMIT) return;
+    }
+
     if ($scope.amountModel.amount && $scope.amountModel.amount.length >= LENGTH_EXPRESSION_LIMIT) return;
     if (($scope.amountModel.amount.indexOf('.') > -1 || $scope.amountModel.amount == '') && digit == '.') return;
     if ($scope.amountModel.amount == '0' && digit == '0') return;
diff --git a/src/js/controllers/tab-scan.js b/src/js/controllers/tab-scan.js
index 1744f3d69..c29be53ad 100644
--- a/src/js/controllers/tab-scan.js
+++ b/src/js/controllers/tab-scan.js
@@ -61,10 +61,7 @@ angular.module('copayApp.controllers').controller('tabScanController', function(
 
   $scope.$on("$ionicView.afterEnter", function() {
     // try initializing and refreshing status any time the view is entered
-    if(!scannerService.isInitialized()){
-      scannerService.gentleInitialize();
-    }
-    activate();
+    scannerService.gentleInitialize();
   });
 
   function activate(){
diff --git a/src/sass/views/amount.scss b/src/sass/views/amount.scss
index 08892c88d..26169f206 100644
--- a/src/sass/views/amount.scss
+++ b/src/sass/views/amount.scss
@@ -337,7 +337,7 @@
             right: 0;
             top: 50%;
             transform: translate(0, -50%);
-            padding: 5px;
+            padding: 15px;
 
             img {
               width: 18px;