diff --git a/lib/certificate_detail.dart b/lib/certificate_detail.dart
index 72f4319..9424679 100644
--- a/lib/certificate_detail.dart
+++ b/lib/certificate_detail.dart
@@ -133,13 +133,13 @@ class CertificateDetail extends StatelessWidget {
         builder: (_) => AlertDialog(
               title: Text('Disable ' + getTitle(cert.data) + '?'),
               content: Text(Platform.isAndroid
-                  ? 'Disabling certificate on Android through third party is not supported by the system.\n\n'
-                      'However, CertainTLS cannot detect if you have disabled any certificates on Android.'
-                  : 'Confirm?'),
+                  ? 'On the next screen, scroll to the "${getTitle(cert.data)}" certificate and disable it.'
+                  : 'Confirm'),
               actions: [
                 FlatButton(
-                    onPressed: () => {Navigator.pop(ctx)}, child: Text('No')),
-                FlatButton(onPressed: () => _distrust(ctx), child: Text('Yes'))
+                    onPressed: () => {Navigator.pop(ctx)},
+                    child: Text('Cancel')),
+                FlatButton(onPressed: () => _distrust(ctx), child: Text('OK'))
               ],
             ),
         barrierDismissible: false);
diff --git a/lib/main.dart b/lib/main.dart
index 909ff2e..ad64650 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -41,7 +41,13 @@ class _MyAppState extends State<MyApp> {
         actions: <Widget>[
           IconButton(
               icon: Icon(Icons.settings),
-              onPressed: () => _showAboutDialog(context))
+              onPressed: () => _showAboutDialog(context)),
+          FlatButton(
+            textColor: Colors.white,
+            onPressed: () => _contactUs(),
+            child: Text("Feedback"),
+            shape: CircleBorder(side: BorderSide(color: Colors.transparent)),
+          )
         ],
       ),
       body: bodies[_selectedIndex],
@@ -111,7 +117,7 @@ class _MyAppState extends State<MyApp> {
         return StatefulBuilder(builder: (context, setState) {
           String userName = prefs.getString('user_name');
           return AboutDialog(
-            applicationVersion: '1.4.2',
+            applicationVersion: '1.4.3',
             applicationIcon: Image.asset('images/logo.png'),
             children: [
               Text(
@@ -169,6 +175,15 @@ class _MyAppState extends State<MyApp> {
       throw 'Could not launch $url';
     }
   }
+
+  void _contactUs() async {
+    const url = 'https://certaintls.app/contact/certaintls_app_feedback';
+    if (await canLaunch(url)) {
+      await launch(url);
+    } else {
+      throw 'Could not launch $url';
+    }
+  }
 }
 
 class DeviceCerts extends StatelessWidget {
diff --git a/pubspec.lock b/pubspec.lock
index 54338f5..5d3395a 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -42,7 +42,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0-nullsafety.1"
+    version: "2.5.0-nullsafety.3"
   basic_utils:
     dependency: "direct main"
     description:
@@ -56,21 +56,21 @@ packages:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   characters:
     dependency: transitive
     description:
       name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.3"
+    version: "1.1.0-nullsafety.5"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   cli_util:
     dependency: transitive
     description:
@@ -84,14 +84,14 @@ packages:
       name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   collection:
     dependency: transitive
     description:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.15.0-nullsafety.3"
+    version: "1.15.0-nullsafety.5"
   convert:
     dependency: transitive
     description:
@@ -126,7 +126,7 @@ packages:
       name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   faker:
     dependency: "direct main"
     description:
@@ -225,7 +225,7 @@ packages:
       name: js
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.6.3-nullsafety.1"
+    version: "0.6.3-nullsafety.3"
   json_annotation:
     dependency: transitive
     description:
@@ -253,14 +253,14 @@ packages:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.10-nullsafety.1"
+    version: "0.12.10-nullsafety.3"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.4"
+    version: "1.3.0-nullsafety.6"
   mime:
     dependency: transitive
     description:
@@ -316,7 +316,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.1"
+    version: "1.8.0-nullsafety.3"
   path_provider_linux:
     dependency: transitive
     description:
@@ -344,7 +344,7 @@ packages:
       name: pedantic
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.10.0-nullsafety.1"
+    version: "1.10.0-nullsafety.3"
   pem:
     dependency: "direct main"
     description:
@@ -386,7 +386,7 @@ packages:
       name: pool
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.0-nullsafety.1"
+    version: "1.5.0-nullsafety.3"
   process:
     dependency: transitive
     description:
@@ -489,77 +489,77 @@ packages:
       name: source_map_stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.2"
+    version: "2.1.0-nullsafety.4"
   source_maps:
     dependency: transitive
     description:
       name: source_maps
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.10.10-nullsafety.1"
+    version: "0.10.10-nullsafety.3"
   source_span:
     dependency: transitive
     description:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0-nullsafety.2"
+    version: "1.8.0-nullsafety.4"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.10.0-nullsafety.2"
+    version: "1.10.0-nullsafety.6"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.1"
+    version: "2.1.0-nullsafety.3"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0-nullsafety.1"
+    version: "1.1.0-nullsafety.3"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.2.0-nullsafety.1"
+    version: "1.2.0-nullsafety.3"
   test:
     dependency: "direct dev"
     description:
       name: test
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.16.0-nullsafety.5"
+    version: "1.16.0-nullsafety.12"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19-nullsafety.2"
+    version: "0.2.19-nullsafety.6"
   test_core:
     dependency: transitive
     description:
       name: test_core
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.3.12-nullsafety.5"
+    version: "0.3.12-nullsafety.11"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.3.0-nullsafety.3"
+    version: "1.3.0-nullsafety.5"
   url_launcher:
     dependency: "direct main"
     description:
@@ -608,7 +608,7 @@ packages:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0-nullsafety.3"
+    version: "2.1.0-nullsafety.5"
   vm_service:
     dependency: transitive
     description:
@@ -659,5 +659,5 @@ packages:
     source: hosted
     version: "2.2.1"
 sdks:
-  dart: ">=2.10.0-110 <=2.11.0-213.0.dev"
+  dart: ">=2.12.0-0.0 <3.0.0"
   flutter: ">=1.22.0 <2.0.0"
diff --git a/pubspec.yaml b/pubspec.yaml
index 2368861..227bf37 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -11,7 +11,7 @@ description: A new Flutter project.
 # In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
 # Read more about iOS versioning at
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
-version: 1.4.2+8
+version: 1.4.3+9
 
 environment:
   sdk: ">=2.2.0 <3.0.0"