diff --git a/Calculator.xcodeproj/project.pbxproj b/Calculator.xcodeproj/project.pbxproj
index b4616d7..6ff3464 100644
--- a/Calculator.xcodeproj/project.pbxproj
+++ b/Calculator.xcodeproj/project.pbxproj
@@ -305,11 +305,13 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_ENTITLEMENTS = Calculator/Calculator.entitlements;
+				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
 				COMBINE_HIDPI_IMAGES = YES;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Calculator/Preview Content\"";
 				DEVELOPMENT_TEAM = 4UQS8N4WUS;
+				ENABLE_HARDENED_RUNTIME = NO;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_FILE = Calculator/Info.plist;
@@ -319,7 +321,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MARKETING_VERSION = 0.5.0;
+				MARKETING_VERSION = 0.5.1;
 				PRODUCT_BUNDLE_IDENTIFIER = anthonyingle.Calculator;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_EMIT_LOC_STRINGS = YES;
@@ -333,11 +335,13 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				CODE_SIGN_ENTITLEMENTS = Calculator/Calculator.entitlements;
+				CODE_SIGN_IDENTITY = "Apple Development";
 				CODE_SIGN_STYLE = Automatic;
 				COMBINE_HIDPI_IMAGES = YES;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Calculator/Preview Content\"";
 				DEVELOPMENT_TEAM = 4UQS8N4WUS;
+				ENABLE_HARDENED_RUNTIME = NO;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_FILE = Calculator/Info.plist;
@@ -347,7 +351,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MARKETING_VERSION = 0.5.0;
+				MARKETING_VERSION = 0.5.1;
 				PRODUCT_BUNDLE_IDENTIFIER = anthonyingle.Calculator;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_EMIT_LOC_STRINGS = YES;
diff --git a/Calculator/Calculator.entitlements b/Calculator/Calculator.entitlements
index f2ef3ae..18aff0c 100644
--- a/Calculator/Calculator.entitlements
+++ b/Calculator/Calculator.entitlements
@@ -2,9 +2,9 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
-    <key>com.apple.security.app-sandbox</key>
-    <true/>
-    <key>com.apple.security.files.user-selected.read-only</key>
-    <true/>
+	<key>com.apple.security.app-sandbox</key>
+	<true/>
+	<key>com.apple.security.files.user-selected.read-only</key>
+	<true/>
 </dict>
 </plist>
diff --git a/Calculator/CalculatorView.swift b/Calculator/CalculatorView.swift
index dacde7e..7e1fc1c 100644
--- a/Calculator/CalculatorView.swift
+++ b/Calculator/CalculatorView.swift
@@ -30,6 +30,7 @@ struct CalculatorView: View {
                                 .onTapGesture {
                                     expression += item.solution
                                 }
+                                .foregroundColor(historyIndex != -1 ? (item.id == history[historyIndex].id ? .blue : .white) : .white)
                             
                             // copy solution button
                             Button {
@@ -84,10 +85,10 @@ struct CalculatorView: View {
                           onTextChange: { newExpression in
             if !history.isEmpty &&
                 (newExpression == "+" ||
-                newExpression == "*" ||
-                newExpression == "/" ||
-                newExpression == "^" ||
-                newExpression == "%")
+                 newExpression == "*" ||
+                 newExpression == "/" ||
+                 newExpression == "^" ||
+                 newExpression == "%")
             {
                 expression.insert(contentsOf: history[0].solution, at: expression.startIndex)
             }
@@ -110,9 +111,8 @@ struct CalculatorView: View {
                 if historyIndex > 0 {
                     expression.removeLast(history[historyIndex - 1].solution.count)
                 }
-                    expression += history[historyIndex].solution
+                expression += history[historyIndex].solution
             }
-            
         },
                           // on DOWN ARROW key
                           onMoveDown: {