diff --git a/.github/workflows/dartdoc.yml b/.github/workflows/dartdoc.yml
index e803d6dffc9..20a699701cd 100644
--- a/.github/workflows/dartdoc.yml
+++ b/.github/workflows/dartdoc.yml
@@ -30,7 +30,7 @@
               run: pub global activate dartdoc && dartdoc
               
             - name: Deploy API documentation to Github Pages
-              uses: JamesIves/github-pages-deploy-action@v4.2.3
+              uses: JamesIves/github-pages-deploy-action@v4.2.5
               with:
                 BRANCH: gh-pages
                 FOLDER: packages/smooth_app/doc/api/
diff --git a/packages/smooth_app/lib/cards/product_cards/knowledge_panels/knowledge_panel_card.dart b/packages/smooth_app/lib/cards/product_cards/knowledge_panels/knowledge_panel_card.dart
index ad26ebffc4c..b1d5fff9dde 100644
--- a/packages/smooth_app/lib/cards/product_cards/knowledge_panels/knowledge_panel_card.dart
+++ b/packages/smooth_app/lib/cards/product_cards/knowledge_panels/knowledge_panel_card.dart
@@ -5,6 +5,7 @@ import 'package:provider/provider.dart';
 import 'package:smooth_app/cards/product_cards/knowledge_panels/knowledge_panel_expanded_card.dart';
 import 'package:smooth_app/cards/product_cards/knowledge_panels/knowledge_panel_summary_card.dart';
 import 'package:smooth_app/generic_lib/widgets/smooth_card.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/helpers/ui_helpers.dart';
 import 'package:smooth_app/themes/smooth_theme.dart';
 import 'package:smooth_app/themes/theme_provider.dart';
@@ -31,31 +32,36 @@ class KnowledgePanelCard extends StatelessWidget {
     }
     return InkWell(
       child: KnowledgePanelSummaryCard(panel),
-      onTap: () => Navigator.push<Widget>(
-        context,
-        MaterialPageRoute<Widget>(
-          builder: (BuildContext context) => Scaffold(
-            backgroundColor: SmoothTheme.getColor(
-              themeData.colorScheme,
-              SmoothTheme.getMaterialColor(themeProvider),
-              ColorDestination.SURFACE_BACKGROUND,
-            ),
-            appBar: AppBar(),
-            body: SingleChildScrollView(
-              child: SmoothCard(
-                color: const Color(0xfff5f6fa),
-                padding: const EdgeInsets.all(
-                  SMALL_SPACE,
-                ),
-                child: KnowledgePanelExpandedCard(
-                  panel: panel,
-                  allPanels: allPanels,
+      onTap: () {
+        AnalyticsHelper.trackKnowledgePanelOpen(
+          knowledgePanelName: panel.topics.toString(),
+        );
+        Navigator.push<Widget>(
+          context,
+          MaterialPageRoute<Widget>(
+            builder: (BuildContext context) => Scaffold(
+              backgroundColor: SmoothTheme.getColor(
+                themeData.colorScheme,
+                SmoothTheme.getMaterialColor(themeProvider),
+                ColorDestination.SURFACE_BACKGROUND,
+              ),
+              appBar: AppBar(),
+              body: SingleChildScrollView(
+                child: SmoothCard(
+                  color: const Color(0xfff5f6fa),
+                  padding: const EdgeInsets.all(
+                    SMALL_SPACE,
+                  ),
+                  child: KnowledgePanelExpandedCard(
+                    panel: panel,
+                    allPanels: allPanels,
+                  ),
                 ),
               ),
             ),
           ),
-        ),
-      ),
+        );
+      },
     );
   }
 }
diff --git a/packages/smooth_app/lib/data_models/continuous_scan_model.dart b/packages/smooth_app/lib/data_models/continuous_scan_model.dart
index 0722742a048..4a0a0eb74a9 100644
--- a/packages/smooth_app/lib/data_models/continuous_scan_model.dart
+++ b/packages/smooth_app/lib/data_models/continuous_scan_model.dart
@@ -7,6 +7,7 @@ import 'package:smooth_app/database/barcode_product_query.dart';
 import 'package:smooth_app/database/dao_product.dart';
 import 'package:smooth_app/database/dao_product_list.dart';
 import 'package:smooth_app/database/local_database.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 
 enum ScannedProductState {
   FOUND,
@@ -32,7 +33,6 @@ class ContinuousScanModel with ChangeNotifier {
   late DaoProduct _daoProduct;
   late DaoProductList _daoProductList;
 
-  bool get hasMoreThanOneProduct => getBarcodes().length > 1;
   ProductList get productList => _productList;
 
   List<String> getBarcodes() => _barcodes;
@@ -99,6 +99,8 @@ class ContinuousScanModel with ChangeNotifier {
     if (_latestScannedBarcode == code) {
       return;
     }
+    AnalyticsHelper.trackScannedProduct(barcode: code);
+
     _latestScannedBarcode = code;
     _addBarcode(code);
   }
diff --git a/packages/smooth_app/lib/data_models/product_query_model.dart b/packages/smooth_app/lib/data_models/product_query_model.dart
index b02ba62174b..4e2c7658132 100644
--- a/packages/smooth_app/lib/data_models/product_query_model.dart
+++ b/packages/smooth_app/lib/data_models/product_query_model.dart
@@ -21,6 +21,7 @@ class ProductQueryModel with ChangeNotifier {
   final ProductListSupplier supplier;
 
   static const String _CATEGORY_ALL = 'all';
+  String currentCategory = _CATEGORY_ALL;
 
   LoadingStatus _loadingStatus = LoadingStatus.LOADING;
   String? _loadingError;
@@ -108,6 +109,7 @@ class ProductQueryModel with ChangeNotifier {
   }
 
   void selectCategory(String category) {
+    currentCategory = category;
     if (category == _CATEGORY_ALL) {
       displayProducts = _products;
     } else {
diff --git a/packages/smooth_app/lib/database/dao_int.dart b/packages/smooth_app/lib/database/dao_int.dart
new file mode 100644
index 00000000000..8cec1f50679
--- /dev/null
+++ b/packages/smooth_app/lib/database/dao_int.dart
@@ -0,0 +1,23 @@
+import 'package:hive_flutter/hive_flutter.dart';
+import 'package:smooth_app/database/abstract_dao.dart';
+import 'package:smooth_app/database/local_database.dart';
+
+/// Where we store ints.
+class DaoInt extends AbstractDao {
+  DaoInt(final LocalDatabase localDatabase) : super(localDatabase);
+
+  static const String _hiveBoxName = 'int';
+
+  @override
+  Future<void> init() async => Hive.openBox<int>(_hiveBoxName);
+
+  @override
+  void registerAdapter() {}
+
+  Box<int> _getBox() => Hive.box<int>(_hiveBoxName);
+
+  int? get(final String key) => _getBox().get(key);
+
+  Future<void> put(final String key, final int? value) async =>
+      value == null ? _getBox().delete(key) : _getBox().put(key, value);
+}
diff --git a/packages/smooth_app/lib/database/local_database.dart b/packages/smooth_app/lib/database/local_database.dart
index d448a927e5d..a3c064befe6 100644
--- a/packages/smooth_app/lib/database/local_database.dart
+++ b/packages/smooth_app/lib/database/local_database.dart
@@ -3,6 +3,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:hive_flutter/hive_flutter.dart';
 import 'package:smooth_app/database/abstract_dao.dart';
+import 'package:smooth_app/database/dao_int.dart';
 import 'package:smooth_app/database/dao_product.dart';
 import 'package:smooth_app/database/dao_product_list.dart';
 import 'package:smooth_app/database/dao_string.dart';
@@ -26,6 +27,7 @@ class LocalDatabase extends ChangeNotifier {
       DaoProductList(localDatabase),
       DaoStringList(localDatabase),
       DaoString(localDatabase),
+      DaoInt(localDatabase),
     ];
     for (final AbstractDao dao in daos) {
       dao.registerAdapter();
diff --git a/packages/smooth_app/lib/helpers/analytics_helper.dart b/packages/smooth_app/lib/helpers/analytics_helper.dart
new file mode 100644
index 00000000000..246d854fcd0
--- /dev/null
+++ b/packages/smooth_app/lib/helpers/analytics_helper.dart
@@ -0,0 +1,225 @@
+import 'dart:async';
+import 'dart:math';
+
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/foundation.dart';
+import 'package:matomo_forever/matomo_forever.dart';
+import 'package:openfoodfacts/model/Product.dart';
+import 'package:openfoodfacts/utils/OpenFoodAPIConfiguration.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+import 'package:sentry_flutter/sentry_flutter.dart';
+import 'package:smooth_app/database/local_database.dart';
+import 'package:smooth_app/helpers/tracking_database_helper.dart';
+
+// TODO(m123): Check for user consent
+
+/// Helper for logging usage of core features and exceptions
+/// Logging:
+/// - Errors and Problems (sentry)
+/// - App start
+/// - Product scan
+/// - Product page open
+/// - Knowledge panel open
+/// - personalized ranking (without sharing the preferences)
+/// - search
+/// - external links
+class AnalyticsHelper {
+  AnalyticsHelper._();
+
+  static const String _initAction = 'started app';
+  static const String _scanAction = 'scanned product';
+  static const String _productPageAction = 'opened product page';
+  static const String _knowledgePanelAction = 'opened knowledge panel page';
+  static const String _personalizedRankingAction = 'personalized ranking';
+  static const String _searchAction = 'search';
+  static const String _linkAction = 'opened link';
+
+  /// The event category. Must not be empty. (eg. Videos, Music, Games...)
+  static const String _eventCategory = 'e_c';
+
+  /// Must not be empty. (eg. Play, Pause, Duration, Add
+  /// Playlist, Downloaded, Clicked...)
+  static const String _eventAction = 'e_a';
+
+  /// The event name. (eg. a Movie name, or Song name, or File name...)
+  static const String _eventName = 'e_n';
+
+  /// Must be a float or integer value (numeric), not a string.
+  static const String _eventValue = 'e_v';
+
+  static String latestSearch = '';
+
+  static Future<void> initSentry({Function()? appRunner}) async {
+    final PackageInfo packageInfo = await PackageInfo.fromPlatform();
+
+    await SentryFlutter.init(
+      (SentryOptions options) {
+        options.dsn =
+            'https://22ec5d0489534b91ba455462d3736680@o241488.ingest.sentry.io/5376745';
+        options.sentryClientName =
+            'sentry.dart.smoothie/${packageInfo.version}';
+      },
+      appRunner: appRunner,
+    );
+  }
+
+  static Future<void> initMatomo(
+    final BuildContext context,
+    final LocalDatabase _localDatabase,
+  ) async {
+    MatomoForever.init(
+      'https://analytics.openfoodfacts.org/matomo.php',
+      2,
+      id: _getId(),
+      // If we track or not, should be decidable later
+      rec: true,
+      method: MatomoForeverMethod.post,
+      sendImage: false,
+      // 32 character authorization key used to authenticate the API request
+      // only needed for request which are more then 24h old
+      // tokenAuth: 'xxx',
+    );
+  }
+
+  static Future<bool> trackStart(
+      LocalDatabase _localDatabase, BuildContext context) async {
+    final TrackingDatabaseHelper trackingDatabaseHelper =
+        TrackingDatabaseHelper(_localDatabase);
+    final Size size = MediaQuery.of(context).size;
+    final Map<String, String> data = <String, String>{};
+
+    // The current count of visits for this visitor
+    data.addIfVAndNew(
+        '_idvc', trackingDatabaseHelper.getAppVisits().toString());
+    // The UNIX timestamp of this visitor's previous visit
+    data.addIfVAndNew(
+      '_viewts',
+      trackingDatabaseHelper.getPreviousVisitUnix().toString(),
+    );
+    // The UNIX timestamp of this visitor's first visit
+    data.addIfVAndNew(
+      '_idts',
+      trackingDatabaseHelper.getFirstVisitUnix().toString(),
+    );
+    // Device resolution
+    data.addIfVAndNew('res', '${size.width}x${size.height}');
+    data.addIfVAndNew('lang', Localizations.localeOf(context).languageCode);
+    data.addIfVAndNew('country', Localizations.localeOf(context).countryCode);
+
+    return _track(
+      _initAction,
+      data,
+    );
+  }
+
+  // TODO(m123): Matomo removes leading 0 from the barcode
+  static Future<bool> trackScannedProduct({required String barcode}) => _track(
+        _scanAction,
+        <String, String>{
+          _eventCategory: 'Scanner',
+          _eventAction: 'Scanned',
+          _eventValue: barcode,
+        },
+      );
+
+  static Future<bool> trackProductPageOpen({
+    required Product product,
+  }) {
+    final Map<String, String> data = <String, String>{
+      _eventCategory: 'Product page',
+      _eventAction: 'opened',
+    };
+    data.addIfVAndNew(_eventValue, product.productName);
+    data.addIfVAndNew(_eventName, product.productName);
+
+    return _track(
+      _productPageAction,
+      data,
+    );
+  }
+
+  static Future<bool> trackKnowledgePanelOpen({
+    String? knowledgePanelName,
+  }) {
+    final Map<String, String> data = <String, String>{
+      _eventCategory: 'Knowledge panel',
+      _eventAction: 'opened',
+    };
+    data.addIfVAndNew(_eventName, knowledgePanelName);
+
+    return _track(
+      _knowledgePanelAction,
+      data,
+    );
+  }
+
+  static Future<bool> trackPersonalizedRanking({
+    required String title,
+    required int products,
+    required int goodProducts,
+    required int badProducts,
+    required int unknownProducts,
+  }) =>
+      _track(
+        _personalizedRankingAction,
+        <String, String>{
+          'title': title,
+          'productsCount': '$products',
+          'goodProducts': '$goodProducts',
+          'badProducts': '$badProducts',
+          'unkownProducts': '$unknownProducts',
+        },
+      );
+
+  static void trackSearch({
+    required String search,
+    String? searchCategory,
+    int? searchCount,
+  }) {
+    final Map<String, String> data = <String, String>{
+      'search': search,
+    };
+    data.addIfVAndNew('search_cat', searchCategory);
+    data.addIfVAndNew('search_count', searchCount);
+
+    if (data.toString() == latestSearch) {
+      return;
+    }
+    latestSearch = data.toString();
+
+    _track(
+      _searchAction,
+      data,
+    );
+  }
+
+  static Future<bool> trackOpenLink({required String url}) => _track(
+        _linkAction,
+        <String, String>{
+          'url': url,
+          'link': url,
+        },
+      );
+
+  static Future<bool> _track(String actionName, Map<String, String> data) {
+    final DateTime date = DateTime.now();
+    final Map<String, String> addedData = <String, String>{
+      'action_name': actionName,
+      //Random number to avoid the tracking request being cached by the browser or a proxy.
+      'rand': Random().nextInt(1000).toString(),
+      //Adding the tracking time
+      'h': date.hour.toString(),
+      'm': date.minute.toString(),
+      's': date.second.toString(),
+    };
+    // User identifier
+    addedData.addIfVAndNew('uid', _getId());
+    addedData.addAll(data);
+
+    return MatomoForever.sendDataOrBulk(addedData);
+  }
+
+  static String? _getId() {
+    return kDebugMode ? 'smoothie-debug' : OpenFoodAPIConfiguration.uuid;
+  }
+}
diff --git a/packages/smooth_app/lib/helpers/launch_url_helper.dart b/packages/smooth_app/lib/helpers/launch_url_helper.dart
index 9c08c933139..3e07060db4a 100644
--- a/packages/smooth_app/lib/helpers/launch_url_helper.dart
+++ b/packages/smooth_app/lib/helpers/launch_url_helper.dart
@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:url_launcher/url_launcher.dart';
 
 class LaunchUrlHelper {
@@ -11,28 +12,36 @@ class LaunchUrlHelper {
   ///
   static Future<void> launchURL(String url, bool isOFF) async {
     if (isOFF) {
-      if (!url.contains('https://openfoodfacts.')) {
-        throw 'Error do not use local identifier in url';
-      }
-
-      String? countryCode = WidgetsBinding.instance == null
-          ? null
-          : WidgetsBinding.instance!.window.locale.countryCode;
-
-      if (countryCode == null) {
-        countryCode = 'world.';
-      } else {
-        countryCode = '$countryCode.';
-      }
-
-      url = url.replaceAll(
-          'https://openfoodfacts.', 'https://${countryCode}openfoodfacts.');
+      url = _replaceSubdomainWithCodes(url);
     }
 
+    AnalyticsHelper.trackOpenLink(url: url);
+
     if (await canLaunch(url)) {
       await launch(url);
     } else {
       throw 'Could not launch $url';
     }
   }
+
+  static String _replaceSubdomainWithCodes(String url) {
+    if (!url.contains('https://openfoodfacts.')) {
+      throw 'Error do not use local identifier in url';
+    }
+
+    String? countryCode = WidgetsBinding.instance == null
+        ? null
+        : WidgetsBinding.instance!.window.locale.countryCode?.toLowerCase();
+
+    if (countryCode == null) {
+      countryCode = 'world.';
+    } else {
+      countryCode = '$countryCode.';
+    }
+
+    url = url.replaceAll(
+        'https://openfoodfacts.', 'https://${countryCode}openfoodfacts.');
+
+    return url;
+  }
 }
diff --git a/packages/smooth_app/lib/helpers/tracking_database_helper.dart b/packages/smooth_app/lib/helpers/tracking_database_helper.dart
new file mode 100644
index 00000000000..0c54e027be1
--- /dev/null
+++ b/packages/smooth_app/lib/helpers/tracking_database_helper.dart
@@ -0,0 +1,52 @@
+import 'package:smooth_app/database/dao_int.dart';
+import 'package:smooth_app/database/local_database.dart';
+
+class TrackingDatabaseHelper {
+  const TrackingDatabaseHelper(this._localDatabase);
+  final LocalDatabase _localDatabase;
+
+  /// Returns the amount the user has opened the app
+  int getAppVisits() {
+    const String _userVisits = 'appVisits';
+
+    final DaoInt daoInt = DaoInt(_localDatabase);
+
+    int visits = daoInt.get(_userVisits) ?? 0;
+    visits++;
+    daoInt.put(_userVisits, visits);
+
+    return visits;
+  }
+
+  int? getPreviousVisitUnix() {
+    const String _latestVisit = 'previousVisitUnix';
+
+    final DaoInt daoInt = DaoInt(_localDatabase);
+
+    final int? latestVisit = daoInt.get(_latestVisit);
+
+    daoInt.put(
+      _latestVisit,
+      DateTime.now().millisecondsSinceEpoch,
+    );
+
+    return latestVisit;
+  }
+
+  int? getFirstVisitUnix() {
+    const String _firstVisit = 'firstVisitUnix';
+
+    final DaoInt daoInt = DaoInt(_localDatabase);
+
+    final int? firstVisit = daoInt.get(_firstVisit);
+
+    if (firstVisit == null) {
+      daoInt.put(
+        _firstVisit,
+        DateTime.now().millisecondsSinceEpoch,
+      );
+    }
+
+    return firstVisit;
+  }
+}
diff --git a/packages/smooth_app/lib/main.dart b/packages/smooth_app/lib/main.dart
index a86fef71a93..b80c46a0484 100644
--- a/packages/smooth_app/lib/main.dart
+++ b/packages/smooth_app/lib/main.dart
@@ -7,7 +7,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 import 'package:openfoodfacts/personalized_search/product_preferences_selection.dart';
-import 'package:package_info_plus/package_info_plus.dart';
 import 'package:provider/provider.dart';
 import 'package:sentry_flutter/sentry_flutter.dart';
 import 'package:smooth_app/data_models/product_preferences.dart';
@@ -15,6 +14,7 @@ import 'package:smooth_app/data_models/user_preferences.dart';
 import 'package:smooth_app/database/dao_string.dart';
 import 'package:smooth_app/database/local_database.dart';
 import 'package:smooth_app/database/product_query.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/helpers/user_management_helper.dart';
 import 'package:smooth_app/pages/onboarding/onboarding_flow_navigator.dart';
 import 'package:smooth_app/themes/smooth_theme.dart';
@@ -24,27 +24,16 @@ List<CameraDescription> cameras = <CameraDescription>[];
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
-  final PackageInfo packageInfo = await PackageInfo.fromPlatform();
 
   if (kReleaseMode) {
-    await SentryFlutter.init(
-      (SentryOptions options) {
-        options.dsn =
-            'https://22ec5d0489534b91ba455462d3736680@o241488.ingest.sentry.io/5376745';
-        options.sentryClientName =
-            'sentry.dart.smoothie/${packageInfo.version}';
-      },
-      appRunner: () => runApp(const SmoothApp()),
-    );
-
-    /* TODO: put back when we have clearer ideas about analytics
-    await MatomoTracker().initialize(
-      siteId: 2,
-      url: 'https://analytics.openfoodfacts.org/',
+    await AnalyticsHelper.initSentry(
+      appRunner: () => const SmoothApp(),
     );
-    */
   } else {
-    runApp(DevicePreview(enabled: true, builder: (_) => const SmoothApp()));
+    runApp(DevicePreview(
+      enabled: true,
+      builder: (_) => const SmoothApp(),
+    ));
   }
 }
 
@@ -95,9 +84,11 @@ class _SmoothAppState extends State<SmoothApp> {
     _themeProvider = ThemeProvider(_userPreferences);
     ProductQuery.setQueryType(_userPreferences);
 
-    UserManagementHelper.mountCredentials();
     cameras = await availableCameras();
+
+    UserManagementHelper.mountCredentials();
     await ProductQuery.setUuid(_localDatabase);
+    await AnalyticsHelper.initMatomo(context, _localDatabase);
   }
 
   @override
@@ -177,11 +168,26 @@ class _SmoothAppState extends State<SmoothApp> {
 
 /// Layer needed because we need to know the language. Language isn't available
 /// in the [context] in top level widget ([SmoothApp])
-class SmoothAppGetLanguage extends StatelessWidget {
+class SmoothAppGetLanguage extends StatefulWidget {
   const SmoothAppGetLanguage(this.appWidget);
 
   final Widget appWidget;
 
+  @override
+  State<SmoothAppGetLanguage> createState() => _SmoothAppGetLanguageState();
+}
+
+// Currently converted into a StatefulWidget to call trackStart in initState
+// since this widget got rebuild multiple time which it shouldn't
+// TODO(open): Fix unnecessary rebuilds
+class _SmoothAppGetLanguageState extends State<SmoothAppGetLanguage> {
+  @override
+  void initState() {
+    final LocalDatabase _localDatabase = context.read<LocalDatabase>();
+    AnalyticsHelper.trackStart(_localDatabase, context);
+    super.initState();
+  }
+
   @override
   Widget build(BuildContext context) {
     final ProductPreferences productPreferences =
@@ -190,6 +196,7 @@ class SmoothAppGetLanguage extends StatelessWidget {
     final String languageCode = myLocale.languageCode;
     ProductQuery.setLanguage(languageCode);
     productPreferences.refresh(languageCode);
-    return appWidget;
+
+    return widget.appWidget;
   }
 }
diff --git a/packages/smooth_app/lib/pages/personalized_ranking_page.dart b/packages/smooth_app/lib/pages/personalized_ranking_page.dart
index 43fd4c4a9bd..cb6d187f08e 100644
--- a/packages/smooth_app/lib/pages/personalized_ranking_page.dart
+++ b/packages/smooth_app/lib/pages/personalized_ranking_page.dart
@@ -9,6 +9,7 @@ import 'package:smooth_app/data_models/smooth_it_model.dart';
 import 'package:smooth_app/data_models/user_preferences.dart';
 import 'package:smooth_app/database/dao_product_list.dart';
 import 'package:smooth_app/database/local_database.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/helpers/smooth_matched_product.dart';
 
 class PersonalizedRankingPage extends StatefulWidget {
@@ -73,6 +74,15 @@ class _PersonalizedRankingPageState extends State<PersonalizedRankingPage> {
       );
       colors.add(_COLORS[matchTab]!);
     }
+
+    AnalyticsHelper.trackPersonalizedRanking(
+      title: widget.title,
+      products: matchedProductsList[0].length,
+      goodProducts: matchedProductsList[1].length,
+      badProducts: matchedProductsList[2].length,
+      unknownProducts: matchedProductsList[3].length,
+    );
+
     return DefaultTabController(
       length: _ORDERED_MATCH_TABS.length,
       initialIndex: _ORDERED_MATCH_TABS.indexOf(MatchTab.YES),
diff --git a/packages/smooth_app/lib/pages/product/common/product_query_page.dart b/packages/smooth_app/lib/pages/product/common/product_query_page.dart
index 89f5b58f2c8..a6107078fb3 100644
--- a/packages/smooth_app/lib/pages/product/common/product_query_page.dart
+++ b/packages/smooth_app/lib/pages/product/common/product_query_page.dart
@@ -7,6 +7,7 @@ import 'package:provider/provider.dart';
 import 'package:smooth_app/cards/product_cards/smooth_product_card_found.dart';
 import 'package:smooth_app/data_models/product_list_supplier.dart';
 import 'package:smooth_app/data_models/product_query_model.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/pages/personalized_ranking_page.dart';
 import 'package:smooth_app/pages/product/common/product_query_page_helper.dart';
 import 'package:smooth_app/themes/constant_icons.dart';
@@ -88,6 +89,11 @@ class _ProductQueryPageState extends State<ProductQueryPage> {
           case LoadingStatus.COMPLETE:
             if (_model.isNotEmpty()) {
               _showRefreshSnackBar(_scaffoldKeyNotEmpty);
+              AnalyticsHelper.trackSearch(
+                search: widget.name,
+                searchCategory: _model.currentCategory,
+                searchCount: _model.displayProducts?.length,
+              );
               return _getNotEmptyScreen(screenSize, themeData);
             }
             _showRefreshSnackBar(_scaffoldKeyEmpty);
diff --git a/packages/smooth_app/lib/pages/product/new_product_page.dart b/packages/smooth_app/lib/pages/product/new_product_page.dart
index f0b243a8b68..9833a9a0316 100644
--- a/packages/smooth_app/lib/pages/product/new_product_page.dart
+++ b/packages/smooth_app/lib/pages/product/new_product_page.dart
@@ -13,6 +13,7 @@ import 'package:smooth_app/database/dao_product_list.dart';
 import 'package:smooth_app/database/knowledge_panels_query.dart';
 import 'package:smooth_app/database/local_database.dart';
 import 'package:smooth_app/database/product_query.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/helpers/launch_url_helper.dart';
 import 'package:smooth_app/helpers/product_cards_helper.dart';
 import 'package:smooth_app/helpers/ui_helpers.dart';
@@ -45,6 +46,9 @@ class _ProductPageState extends State<ProductPage> {
     super.initState();
     _product = widget.product;
     _updateLocalDatabaseWithProductHistory(context, _product);
+    AnalyticsHelper.trackProductPageOpen(
+      product: _product,
+    );
   }
 
   @override
diff --git a/packages/smooth_app/lib/pages/product/nutrition_container.dart b/packages/smooth_app/lib/pages/product/nutrition_container.dart
new file mode 100644
index 00000000000..6ac9b28edbe
--- /dev/null
+++ b/packages/smooth_app/lib/pages/product/nutrition_container.dart
@@ -0,0 +1,318 @@
+import 'package:openfoodfacts/interface/JsonObject.dart';
+import 'package:openfoodfacts/model/Nutriments.dart';
+import 'package:openfoodfacts/model/OrderedNutrient.dart';
+import 'package:openfoodfacts/model/OrderedNutrients.dart';
+import 'package:openfoodfacts/model/Product.dart';
+import 'package:openfoodfacts/utils/UnitHelper.dart';
+import 'package:smooth_app/pages/product/tmp_to_off_nutriments.dart';
+
+/// Nutrition data, for nutrient order and conversions.
+class NutritionContainer {
+  NutritionContainer({
+    required final OrderedNutrients orderedNutrients,
+    required final Product product,
+  }) {
+    _loadNutrients(orderedNutrients.nutrients);
+    final Map<String, dynamic>? json = product.nutriments?.toJson();
+    if (json != null) {
+      _loadUnits(json);
+      _loadValues(json);
+    }
+    _servingSize = product.servingSize;
+    _barcode = product.barcode!;
+  }
+
+  static const String _energyId = 'energy';
+
+  /// special case: present id [OrderedNutrient] but not in [Nutriments] map.
+  static const String _energyKJId = 'energy-kj';
+  static const String _energyKCalId = 'energy-kcal';
+  static const String fakeNutrientIdServingSize = '_servingSize';
+
+  static const Map<Unit, Unit> _nextWeightUnits = <Unit, Unit>{
+    Unit.G: Unit.MILLI_G,
+    Unit.MILLI_G: Unit.MICRO_G,
+    Unit.MICRO_G: Unit.G,
+  };
+
+  // For the moment we only care about "weight or not weight?"
+  // Could be refined with values taken from https://static.openfoodfacts.org/data/taxonomies/nutrients.json
+  // Fun fact: most of them are not supported (yet) by [Nutriments].
+  static const Map<String, Unit> _defaultNotWeightUnits = <String, Unit>{
+    _energyId: Unit.KJ,
+    _energyKCalId: Unit.KCAL,
+    'alcohol': Unit.PERCENT,
+    'cocoa': Unit.PERCENT,
+    'collagen-meat-protein-ratio': Unit.PERCENT,
+    'fruits-vegetables-nuts': Unit.PERCENT,
+    'fruits-vegetables-nuts-dried': Unit.PERCENT,
+    'fruits-vegetables-nuts-estimate': Unit.PERCENT,
+  };
+
+  /// All the nutrients (country-related).
+  final List<OrderedNutrient> _nutrients = <OrderedNutrient>[];
+
+  /// Nutrient values for 100g and serving.
+  final Map<String, double> _values = <String, double>{};
+
+  /// Nutrient units.
+  final Map<String, Unit> _units = <String, Unit>{};
+
+  /// Nutrient Ids added by the end-user
+  final Set<String> _added = <String>{};
+
+  String? _servingSize;
+
+  String? get servingSize => _servingSize;
+
+  late final String _barcode;
+
+  /// Returns the not interesting nutrients, for a "Please add me!" list.
+  Iterable<OrderedNutrient> getLeftoverNutrients() => _nutrients.where(
+        (final OrderedNutrient element) => _isNotRelevant(element),
+      );
+
+  /// Returns the interesting nutrients that need to be displayed.
+  Iterable<OrderedNutrient> getDisplayableNutrients() => _nutrients.where(
+        (final OrderedNutrient element) => !_isNotRelevant(element),
+      );
+
+  /// Returns true if the [OrderedNutrient] is not relevant.
+  bool _isNotRelevant(final OrderedNutrient orderedNutrient) {
+    final String nutrientId = orderedNutrient.id;
+    final double? value100g = getValue(getValueKey(nutrientId, false));
+    final double? valueServing = getValue(getValueKey(nutrientId, true));
+    return value100g == null &&
+        valueServing == null &&
+        (!orderedNutrient.important) &&
+        (!_added.contains(nutrientId));
+  }
+
+  /// Returns a [Product] with only nutrients data.
+  Product getProduct() => Product(
+        barcode: _barcode,
+        nutriments: _getNutriments(),
+        servingSize: _servingSize,
+      );
+
+  /// Converts all the data to a [Nutriments].
+  Nutriments _getNutriments() {
+    /// Converts a (weight) value to grams (before sending a value to the BE)
+    double? _convertWeightToG(final double? value, final Unit unit) {
+      if (value == null) {
+        return null;
+      }
+      if (unit == Unit.MILLI_G) {
+        return value / 1E3;
+      }
+      if (unit == Unit.MICRO_G) {
+        return value / 1E6;
+      }
+      return value;
+    }
+
+    final Map<String, dynamic> map = <String, dynamic>{};
+    for (final OrderedNutrient orderedNutrient in getDisplayableNutrients()) {
+      final String nutrientId = orderedNutrient.id;
+      final String key100g = getValueKey(nutrientId, false);
+      final String keyServing = getValueKey(nutrientId, true);
+      final double? value100g = getValue(key100g);
+      final double? valueServing = getValue(keyServing);
+      if (value100g == null && valueServing == null) {
+        continue;
+      }
+      final Unit unit = getUnit(nutrientId);
+      if (value100g != null) {
+        map[key100g] = _convertWeightToG(value100g, unit);
+      }
+      if (valueServing != null) {
+        //map[keyServing] = _convertWeightToG(valueServing, unit);
+      }
+      map[_getNutrimentsUnitKey(nutrientId)] = UnitHelper.unitToString(unit);
+    }
+
+    return Nutriments.fromJson(map);
+  }
+
+  /// Returns the stored product nutrient's value.
+  double? getValue(final String valueKey) => _values[valueKey];
+
+  /// Stores the text from the end-user input.
+  void setControllerText(final String controllerKey, final String text) {
+    if (controllerKey == fakeNutrientIdServingSize) {
+      _servingSize = text.trim().isEmpty ? null : text;
+      return;
+    }
+
+    double? value;
+    if (text.isNotEmpty) {
+      try {
+        value = double.parse(text.replaceAll(',', '.'));
+      } catch (e) {
+        //
+      }
+    }
+    if (value == null) {
+      _values.remove(controllerKey);
+    } else {
+      _values[controllerKey] = value;
+    }
+  }
+
+  /// Typical use-case: should we make the [Unit] button clickable?
+  static bool isEditableWeight(final OrderedNutrient orderedNutrient) =>
+      _getDefaultUnit(orderedNutrient.id) == null;
+
+  /// Typical use-case: [Unit] button action.
+  void setNextWeightUnit(final OrderedNutrient orderedNutrient) {
+    final Unit unit = getUnit(orderedNutrient.id);
+    _setUnit(orderedNutrient.id, _nextWeightUnits[unit] ?? unit);
+  }
+
+  /// Returns the nutrient [Unit], after possible alterations.
+  Unit getUnit(String nutrientId) {
+    nutrientId = _fixNutrientId(nutrientId);
+    switch (nutrientId) {
+      case _energyId:
+      case _energyKJId:
+        return Unit.KJ;
+      case _energyKCalId:
+        return Unit.KCAL;
+      default:
+        return _units[nutrientId] ?? _getDefaultUnit(nutrientId) ?? Unit.G;
+    }
+  }
+
+  /// Stores the nutrient [Unit].
+  void _setUnit(final String nutrientId, final Unit unit) =>
+      _units[_fixNutrientId(nutrientId)] = unit;
+
+  static Unit? _getDefaultUnit(final String nutrientId) =>
+      _defaultNotWeightUnits[_fixNutrientId(nutrientId)];
+
+  /// To be used when an [OrderedNutrient] is added to the input list
+  void add(final OrderedNutrient orderedNutrient) =>
+      _added.add(orderedNutrient.id);
+
+  /// Returns the [Nutriments] map key for the nutrient value.
+  ///
+  /// * [perServing] true: per serving.
+  /// * [perServing] false: per 100g.
+  static String getValueKey(
+    String nutrientId,
+    final bool perServing,
+  ) {
+    nutrientId = _fixNutrientId(nutrientId);
+    // 'energy-kcal' is directly for serving (no 'energy-kcal_serving')
+    if (nutrientId == _energyKCalId && perServing) {
+      return _energyKCalId;
+    }
+    return '$nutrientId${perServing ? '_serving' : '_100g'}';
+  }
+
+  /// Returns a vertical list of nutrients from a tree structure.
+  ///
+  /// Typical use-case: to be used from BE's tree nutrients in order to get
+  /// a simple one-dimension list, easier to display and parse.
+  /// For some countries, there's energy or energyKJ, or both
+  /// cf. https://github.com/openfoodfacts/openfoodfacts-server/blob/main/lib/ProductOpener/Food.pm
+  /// Regarding our list of nutrients here, we need one and only one of them.
+  void _loadNutrients(
+    final List<OrderedNutrient> nutrients,
+  ) {
+    bool alreadyEnergyKJ = false;
+
+    // inner method, in order to use alreadyEnergyKJ without a private variable.
+    void _populateOrderedNutrientList(final List<OrderedNutrient> list) {
+      for (final OrderedNutrient nutrient in list) {
+        if (nutrient.id != _energyKJId &&
+            !TmpToOffNutriments.supportedNutrientIds.contains(nutrient.id)) {
+          continue;
+        }
+        final bool nowEnergy =
+            nutrient.id == _energyId || nutrient.id == _energyKJId;
+        bool addNutrient = true;
+        if (nowEnergy) {
+          if (alreadyEnergyKJ) {
+            addNutrient = false;
+          }
+          alreadyEnergyKJ = true;
+        }
+        if (addNutrient) {
+          _nutrients.add(nutrient);
+        }
+        if (nutrient.subNutrients != null) {
+          _populateOrderedNutrientList(nutrient.subNutrients!);
+        }
+      }
+    }
+
+    _populateOrderedNutrientList(nutrients);
+
+    if (!alreadyEnergyKJ) {
+      throw Exception('no energy or energyKJ found: very suspicious!');
+    }
+  }
+
+  /// Returns the unit key according to [Nutriments] json map.
+  static String _getNutrimentsUnitKey(final String nutrientId) =>
+      '${_fixNutrientId(nutrientId)}_unit';
+
+  static String _fixNutrientId(final String nutrientId) =>
+      nutrientId == _energyKJId ? _energyId : nutrientId;
+
+  /// Loads product nutrient units into a map.
+  ///
+  /// Needs nutrients to be loaded first.
+  void _loadUnits(final Map<String, dynamic> json) {
+    for (final OrderedNutrient orderedNutrient in _nutrients) {
+      final String nutrientId = orderedNutrient.id;
+      final String unitKey = _getNutrimentsUnitKey(nutrientId);
+      final dynamic value = json[unitKey];
+      if (value == null || value is! String) {
+        continue;
+      }
+      final Unit? unit = UnitHelper.stringToUnit(value);
+      if (unit != null) {
+        _setUnit(nutrientId, unit);
+      }
+    }
+  }
+
+  /// Loads product nutrients into a map.
+  ///
+  /// Needs nutrients and units to be loaded first.
+  void _loadValues(final Map<String, dynamic> json) {
+    /// Converts a double (weight) value from grams.
+    ///
+    /// Typical use-case: after receiving a value from the BE.
+    double? _convertWeightFromG(final double? value, final Unit unit) {
+      if (value == null) {
+        return null;
+      }
+      if (unit == Unit.MILLI_G) {
+        return value * 1E3;
+      }
+      if (unit == Unit.MICRO_G) {
+        return value * 1E6;
+      }
+      return value;
+    }
+
+    for (final OrderedNutrient orderedNutrient in _nutrients) {
+      final String nutrientId = orderedNutrient.id;
+      final Unit unit = getUnit(nutrientId);
+      for (int i = 0; i < 2; i++) {
+        final bool perServing = i == 0;
+        final String valueKey = getValueKey(nutrientId, perServing);
+        final double? value = _convertWeightFromG(
+          JsonObject.parseDouble(json[valueKey]),
+          unit,
+        );
+        if (value != null) {
+          _values[valueKey] = value;
+        }
+      }
+    }
+  }
+}
diff --git a/packages/smooth_app/lib/pages/product/nutrition_page_loaded.dart b/packages/smooth_app/lib/pages/product/nutrition_page_loaded.dart
index d8cb74145f3..f501b02d8f6 100644
--- a/packages/smooth_app/lib/pages/product/nutrition_page_loaded.dart
+++ b/packages/smooth_app/lib/pages/product/nutrition_page_loaded.dart
@@ -2,8 +2,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 import 'package:intl/intl.dart';
-import 'package:openfoodfacts/interface/JsonObject.dart';
-import 'package:openfoodfacts/model/Nutriments.dart';
 import 'package:openfoodfacts/model/OrderedNutrient.dart';
 import 'package:openfoodfacts/model/OrderedNutrients.dart';
 import 'package:openfoodfacts/openfoodfacts.dart';
@@ -13,6 +11,7 @@ import 'package:smooth_app/database/local_database.dart';
 import 'package:smooth_app/database/product_query.dart';
 import 'package:smooth_app/helpers/ui_helpers.dart';
 import 'package:smooth_app/pages/product/common/product_refresher.dart';
+import 'package:smooth_app/pages/product/nutrition_container.dart';
 
 /// Actual nutrition page, with data already loaded.
 class NutritionPageLoaded extends StatefulWidget {
@@ -26,47 +25,29 @@ class NutritionPageLoaded extends StatefulWidget {
 }
 
 class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
-  final List<OrderedNutrient> _displayableList = <OrderedNutrient>[];
-  late Map<String, dynamic> _values;
-  late RegExp _decimalRegExp;
-  late NumberFormat _numberFormat;
+  late final RegExp _decimalRegExp;
+  late final NumberFormat _numberFormat;
+  late final NutritionContainer _nutritionContainer;
 
   bool _unspecified = false; // TODO(monsieurtanuki): fetch that data from API?
+  // If true then serving, if false then 100g.
   bool _servingOr100g = false;
 
   static const double _columnSize1 = 250; // TODO(monsieurtanuki): proper size
   static const double _columnSize2 =
       100; // TODO(monsieurtanuki): anyway, should fit the largest text, probably 'mcg/µg'
 
-  static const String _fakeNutrientIdServingSize = '_servingSize';
-  static const String _energyId = 'energy';
-  static const String _energyKJId = 'energy-kj';
-  static const String _energyKCalId = 'energy-kcal';
-
   final Map<String, TextEditingController> _controllers =
       <String, TextEditingController>{};
-  final Map<String, Unit> _units = <String, Unit>{};
   final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
 
-  static const Map<Unit, Unit> _nextWeightUnits = <Unit, Unit>{
-    Unit.G: Unit.MILLI_G,
-    Unit.MILLI_G: Unit.MICRO_G,
-    Unit.MICRO_G: Unit.G,
-  };
-  static const Map<Unit, String> _unitLabels = <Unit, String>{
-    Unit.G: 'g',
-    Unit.MILLI_G: 'mg',
-    Unit.MICRO_G: 'mcg/µg',
-    Unit.KJ: 'kJ',
-    Unit.KCAL: 'kcal',
-    Unit.PERCENT: '%',
-  };
-
   @override
   void initState() {
     super.initState();
-    _populateOrderedNutrientList(widget.orderedNutrients.nutrients);
-    _values = widget.product.nutriments!.toJson();
+    _nutritionContainer = NutritionContainer(
+      orderedNutrients: widget.orderedNutrients,
+      product: widget.product,
+    );
     _numberFormat = NumberFormat('####0.#####', ProductQuery.getLocaleString());
     _decimalRegExp = _numberFormat.format(1.2).contains('.')
         ? RegExp(r'[0-9\.]') // TODO(monsieurtanuki): check if . or \.
@@ -90,14 +71,14 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
     if (!_unspecified) {
       children.add(_getServingField(appLocalizations));
       children.add(_getServingSwitch(appLocalizations));
-      for (final OrderedNutrient orderedNutrient in _displayableList) {
-        final Widget? item = _getNutrientWidget(
-          appLocalizations,
-          orderedNutrient,
+      for (final OrderedNutrient orderedNutrient
+          in _nutritionContainer.getDisplayableNutrients()) {
+        children.add(
+          _getNutrientRow(
+            appLocalizations,
+            orderedNutrient,
+          ),
         );
-        if (item != null) {
-          children.add(item);
-        }
       }
       children.add(_addNutrientButton(appLocalizations));
     }
@@ -118,85 +99,46 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
     );
   }
 
-  void _populateOrderedNutrientList(final List<OrderedNutrient>? list) {
-    if (list == null) {
-      return;
-    }
-    for (final OrderedNutrient nutrient in list) {
-      _displayableList.add(nutrient);
-      _populateOrderedNutrientList(nutrient.subNutrients);
-    }
-  }
-
-  Widget? _getNutrientWidget(
+  Widget _getNutrientRow(
     final AppLocalizations appLocalizations,
     final OrderedNutrient orderedNutrient,
-  ) {
-    final String id = orderedNutrient.id;
-    if (id == _energyId) {
-      // we keep only kj and kcal
-      return null;
-    }
-    final double? value100g = _getValue(id, false);
-    final double? valueServing = _getValue(id, true);
-    if (value100g == null &&
-        valueServing == null &&
-        !orderedNutrient.important) {
-      return null;
-    }
-    return Row(
-      mainAxisAlignment: MainAxisAlignment.spaceBetween,
-      crossAxisAlignment: CrossAxisAlignment.center,
-      children: <Widget>[
-        SizedBox(
-          width: _columnSize1,
-          child: _getNutrientCell(
-            appLocalizations,
-            orderedNutrient,
-            _servingOr100g,
+  ) =>
+      Row(
+        mainAxisAlignment: MainAxisAlignment.spaceBetween,
+        crossAxisAlignment: CrossAxisAlignment.center,
+        children: <Widget>[
+          SizedBox(
+            width: _columnSize1,
+            child: _getNutrientCell(
+              appLocalizations,
+              orderedNutrient,
+              _servingOr100g,
+            ),
           ),
-        ),
-        SizedBox(
-          width: _columnSize2,
-          child: _getUnitCell(id),
-        ),
-      ],
-    );
-  }
+          SizedBox(
+            width: _columnSize2,
+            child: _getUnitCell(orderedNutrient),
+          ),
+        ],
+      );
 
   Widget _getNutrientCell(
     final AppLocalizations appLocalizations,
     final OrderedNutrient orderedNutrient,
     final bool perServing,
   ) {
-    final String id = orderedNutrient.id;
-    final String tag = _getNutrientServingTag(id, perServing);
+    final String valueKey = NutritionContainer.getValueKey(
+      orderedNutrient.id,
+      perServing,
+    );
     final TextEditingController controller;
-    if (_controllers[tag] != null) {
-      controller = _controllers[tag]!;
+    if (_controllers[valueKey] != null) {
+      controller = _controllers[valueKey]!;
     } else {
-      double? value = _getValue(id, perServing);
-      final Unit? defaultNotWeightUnit = _getDefaultNotWeightUnit(id);
-      final Unit unit = _getUnit(id) ?? defaultNotWeightUnit ?? Unit.G;
-      if (value == null) {
-        if (id == _energyKJId || id == _energyKCalId) {
-          final double? valueEnergy = _getValue(_energyId, perServing);
-          final Unit? unitEnergy = _getUnit(_energyId);
-          if (id == _energyKJId) {
-            if (unitEnergy == Unit.KJ) {
-              value = valueEnergy;
-            }
-          } else if (id == _energyKCalId) {
-            if (unitEnergy == Unit.KCAL) {
-              value = valueEnergy;
-            }
-          }
-        }
-      }
-      value = _convertValueFromG(value, unit);
+      final double? value = _nutritionContainer.getValue(valueKey);
       controller = TextEditingController();
       controller.text = value == null ? '' : _numberFormat.format(value);
-      _controllers[tag] = controller;
+      _controllers[valueKey] = controller;
     }
     return TextFormField(
       controller: controller,
@@ -227,24 +169,24 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
     );
   }
 
-  Widget _getUnitCell(final String nutrientId) {
-    final Unit? defaultNotWeightUnit = _getDefaultNotWeightUnit(nutrientId);
-    final bool isWeight = defaultNotWeightUnit == null;
-    final Unit unit;
-    final String tag = _getNutrientIdFromServingTag(nutrientId);
-    if (_units[tag] != null) {
-      unit = _units[tag]!;
-    } else {
-      unit = _getUnit(nutrientId) ?? defaultNotWeightUnit ?? Unit.G;
-      _units[tag] = unit;
-    }
+  static const Map<Unit, String> _unitLabels = <Unit, String>{
+    Unit.G: 'g',
+    Unit.MILLI_G: 'mg',
+    Unit.MICRO_G: 'mcg/µg',
+    Unit.KJ: 'kJ',
+    Unit.KCAL: 'kcal',
+    Unit.PERCENT: '%',
+  };
+
+  static String _getUnitLabel(final Unit unit) =>
+      _unitLabels[unit] ?? UnitHelper.unitToString(unit)!;
+
+  Widget _getUnitCell(final OrderedNutrient orderedNutrient) {
+    final Unit unit = _nutritionContainer.getUnit(orderedNutrient.id);
     return ElevatedButton(
-      onPressed: isWeight
+      onPressed: NutritionContainer.isEditableWeight(orderedNutrient)
           ? () => setState(
-                () => _setUnit(
-                  nutrientId,
-                  _units[nutrientId] = _nextWeightUnits[unit]!,
-                ),
+                () => _nutritionContainer.setNextWeightUnit(orderedNutrient),
               )
           : null,
       child: Text(
@@ -256,8 +198,8 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
 
   Widget _getServingField(final AppLocalizations appLocalizations) {
     final TextEditingController controller = TextEditingController();
-    controller.text = widget.product.servingSize ?? '';
-    _controllers[_fakeNutrientIdServingSize] = controller;
+    controller.text = _nutritionContainer.servingSize ?? '';
+    _controllers[NutritionContainer.fakeNutrientIdServingSize] = controller;
     return Padding(
       padding: const EdgeInsets.only(bottom: VERY_LARGE_SPACE),
       child: TextFormField(
@@ -286,80 +228,6 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
         ],
       );
 
-  Unit? _getUnit(final String nutrientId) => UnitHelper.stringToUnit(
-        _values[_getUnitValueTag(nutrientId)] as String?,
-      );
-
-  double? _getValue(final String nutrientId, final bool perServing) =>
-      JsonObject.parseDouble(
-          _values[_getNutrientServingTag(nutrientId, perServing)]);
-
-  void _initValues(final String nutrientId) =>
-      _values[_getNutrientServingTag(nutrientId, true)] =
-          _values[_getNutrientServingTag(nutrientId, false)] = 0;
-
-  void _setUnit(final String nutrientId, final Unit unit) =>
-      _values[_getUnitValueTag(nutrientId)] = UnitHelper.unitToString(unit);
-
-  String _getUnitValueTag(final String nutrientId) => '${nutrientId}_unit';
-
-  // note: 'energy-kcal' is directly for serving (no 'energy-kcal_serving')
-  String _getNutrientServingTag(
-    final String nutrientId,
-    final bool perServing,
-  ) =>
-      nutrientId == _energyKCalId && perServing
-          ? _energyKCalId
-          : '$nutrientId${perServing ? '_serving' : '_100g'}';
-
-  String _getNutrientIdFromServingTag(final String key) =>
-      key.replaceAll('_100g', '').replaceAll('_serving', '');
-
-  String _getUnitLabel(final Unit unit) =>
-      _unitLabels[unit] ?? UnitHelper.unitToString(unit)!;
-
-  // For the moment we only care about "weight or not weight?"
-  static const Map<String, Unit> _defaultNotWeightUnits = <String, Unit>{
-    _energyKJId: Unit.KJ,
-    _energyKCalId: Unit.KCAL,
-    'alcohol': Unit.PERCENT,
-    'cocoa': Unit.PERCENT,
-    'collagen-meat-protein-ratio': Unit.PERCENT,
-    'fruits-vegetables-nuts': Unit.PERCENT,
-    'fruits-vegetables-nuts-dried': Unit.PERCENT,
-    'fruits-vegetables-nuts-estimate': Unit.PERCENT,
-  };
-
-  // TODO(monsieurtanuki): could be refined with values taken from https://static.openfoodfacts.org/data/taxonomies/nutrients.json
-  Unit? _getDefaultNotWeightUnit(final String nutrientId) =>
-      _defaultNotWeightUnits[nutrientId];
-
-  double? _convertValueFromG(final double? value, final Unit unit) {
-    if (value == null) {
-      return null;
-    }
-    if (unit == Unit.MILLI_G) {
-      return value * 1E3;
-    }
-    if (unit == Unit.MICRO_G) {
-      return value * 1E6;
-    }
-    return value;
-  }
-
-  double? _convertValueToG(final double? value, final Unit unit) {
-    if (value == null) {
-      return null;
-    }
-    if (unit == Unit.MILLI_G) {
-      return value / 1E3;
-    }
-    if (unit == Unit.MICRO_G) {
-      return value / 1E6;
-    }
-    return value;
-  }
-
   Widget _switchNoNutrition(final AppLocalizations appLocalizations) =>
       Container(
         color: Theme.of(context).colorScheme.primary,
@@ -388,25 +256,16 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
   Widget _addNutrientButton(final AppLocalizations appLocalizations) =>
       ElevatedButton.icon(
         onPressed: () async {
-          final List<OrderedNutrient> availables = <OrderedNutrient>[];
-          for (final OrderedNutrient orderedNutrient in _displayableList) {
-            final String id = orderedNutrient.id;
-            final double? value100g = _getValue(id, false);
-            final double? valueServing = _getValue(id, true);
-            final bool addAble = value100g == null &&
-                valueServing == null &&
-                !orderedNutrient.important;
-            if (addAble) {
-              availables.add(orderedNutrient);
-            }
-          }
-          availables.sort((final OrderedNutrient a, final OrderedNutrient b) =>
+          final List<OrderedNutrient> leftovers = List<OrderedNutrient>.from(
+            _nutritionContainer.getLeftoverNutrients(),
+          );
+          leftovers.sort((final OrderedNutrient a, final OrderedNutrient b) =>
               a.name!.compareTo(b.name!));
           final OrderedNutrient? selected = await showDialog<OrderedNutrient>(
               context: context,
               builder: (BuildContext context) {
                 final List<Widget> children = <Widget>[];
-                for (final OrderedNutrient nutrient in availables) {
+                for (final OrderedNutrient nutrient in leftovers) {
                   children.add(
                     ListTile(
                       title: Text(nutrient.name!),
@@ -431,7 +290,7 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
                 );
               });
           if (selected != null) {
-            setState(() => _initValues(selected.id));
+            setState(() => _nutritionContainer.add(selected));
           }
         },
         icon: const Icon(Icons.add),
@@ -463,24 +322,10 @@ class _NutritionPageLoadedState extends State<NutritionPageLoaded> {
       );
 
   Future<void> _save(final LocalDatabase localDatabase) async {
-    final Map<String, dynamic> map = <String, dynamic>{};
-    String? servingSize;
     for (final String key in _controllers.keys) {
       final TextEditingController controller = _controllers[key]!;
-      final String text = controller.text;
-      if (key == _fakeNutrientIdServingSize) {
-        servingSize = text;
-      } else {
-        if (text.isNotEmpty) {
-          final String nutrientId = _getNutrientIdFromServingTag(key);
-          final Unit unit = _units[nutrientId]!;
-          map[_getUnitValueTag(nutrientId)] = UnitHelper.unitToString(unit);
-          map[key] = _convertValueToG(
-              _numberFormat.parse(text).toDouble(), unit); // careful with comma
-        }
-      }
+      _nutritionContainer.setControllerText(key, controller.text);
     }
-    final Nutriments nutriments = Nutriments.fromJson(map);
     // minimal product: we only want to save the nutrients
     final Product inputProduct = Product(
       barcode: widget.product.barcode,
diff --git a/packages/smooth_app/lib/pages/product/tmp_to_off_nutriments.dart b/packages/smooth_app/lib/pages/product/tmp_to_off_nutriments.dart
new file mode 100644
index 00000000000..9c8af6d40bf
--- /dev/null
+++ b/packages/smooth_app/lib/pages/product/tmp_to_off_nutriments.dart
@@ -0,0 +1,69 @@
+// TODO(monsieurtanuki): move to off-dart
+class TmpToOffNutriments {
+  /// Nutrient ids supported by [Nutriments].
+  ///
+  /// To be used when another source of nutrients (e.g. [OrderedNutrient])
+  /// has a broader list of nutrients - that we simply could not handle with
+  /// [Nutriments].
+  static const Set<String> supportedNutrientIds = <String>{
+    'salt',
+    'fiber',
+    'sugars',
+    'fat',
+    'saturated-fat',
+    'proteins',
+    'nova-group',
+    'energy',
+    'energy-kcal',
+    'carbohydrates',
+    'caffeine',
+    'calcium',
+    'iron',
+    'vitamin-c',
+    'magnesium',
+    'phosphorus',
+    'potassium',
+    'sodium',
+    'zinc',
+    'copper',
+    'selenium',
+    'vitamin-a',
+    'vitamin-e',
+    'vitamin-d',
+    'vitamin-b1',
+    'vitamin-b2',
+    'vitamin-pp',
+    'vitamin-b6',
+    'vitamin-b12',
+    'vitamin-b9',
+    'vitamin-k',
+    'cholesterol',
+    'butyric-acid',
+    'caproic-acid',
+    'caprylic-acid',
+    'capric-acid',
+    'lauric-acid',
+    'myristic-acid',
+    'palmitic-acid',
+    'stearic-acid',
+    'oleic-acid',
+    'linoleic-acid',
+    'docosahexaenoic-acid',
+    'eicosapentaenoic-acid',
+    'erucic-acid',
+    'monounsaturated',
+    'polyunsaturated',
+    'alcohol',
+    'pantothenic-acid',
+    'biotin',
+    'chloride',
+    'chromium',
+    'fluoride',
+    'iodine',
+    'manganese',
+    'molybdenum',
+    'omega-3-fat',
+    'omega-6-fat',
+    'trans-fat',
+  };
+}
diff --git a/packages/smooth_app/lib/pages/scan/scan_header.dart b/packages/smooth_app/lib/pages/scan/scan_header.dart
new file mode 100644
index 00000000000..b2b7903089f
--- /dev/null
+++ b/packages/smooth_app/lib/pages/scan/scan_header.dart
@@ -0,0 +1,62 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_gen/gen_l10n/app_localizations.dart';
+import 'package:provider/provider.dart';
+import 'package:smooth_app/data_models/continuous_scan_model.dart';
+import 'package:smooth_app/helpers/ui_helpers.dart';
+import 'package:smooth_app/pages/scan/scan_page_helper.dart';
+import 'package:smooth_app/widgets/ranking_floating_action_button.dart';
+
+class ScanHeader extends StatelessWidget {
+  const ScanHeader({Key? key}) : super(key: key);
+
+  static const Duration _duration = Duration(milliseconds: 50);
+  static const double _visibleOpacity = 0.8;
+  static const double _invisibleOpacity = 0.0;
+
+  @override
+  Widget build(BuildContext context) {
+    final AppLocalizations appLocalizations = AppLocalizations.of(context)!;
+    final ContinuousScanModel model = context.watch<ContinuousScanModel>();
+
+    final ButtonStyle buttonStyle = ButtonStyle(
+      shape: MaterialStateProperty.all<RoundedRectangleBorder>(
+        RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(18.0),
+        ),
+      ),
+    );
+
+    return AnimatedOpacity(
+      opacity:
+          model.getBarcodes().isNotEmpty ? _visibleOpacity : _invisibleOpacity,
+      duration: _duration,
+      child: Padding(
+        padding: const EdgeInsets.symmetric(
+          vertical: VERY_SMALL_SPACE,
+          horizontal: MEDIUM_SPACE,
+        ),
+        child: Row(
+          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+          children: <Widget>[
+            ElevatedButton.icon(
+              style: buttonStyle,
+              icon: const Icon(Icons.cancel_outlined),
+              onPressed: model.clearScanSession,
+              label: Text(appLocalizations.clear),
+            ),
+            ElevatedButton.icon(
+              style: buttonStyle,
+              icon: const Icon(RankingFloatingActionButton.rankingIconData),
+              onPressed: () => openPersonalizedRankingPage(context),
+              label: Text(
+                appLocalizations.plural_compare_x_products(
+                  model.getBarcodes().length,
+                ),
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
diff --git a/packages/smooth_app/lib/pages/scan/scan_page.dart b/packages/smooth_app/lib/pages/scan/scan_page.dart
index 1a465c11244..cde74ff46c7 100644
--- a/packages/smooth_app/lib/pages/scan/scan_page.dart
+++ b/packages/smooth_app/lib/pages/scan/scan_page.dart
@@ -99,7 +99,6 @@ class _ScanPageState extends State<ScanPage> {
           child: Scaffold(
             body: ScannerOverlay(
               child: child,
-              model: _model!,
             ),
           ),
         );
diff --git a/packages/smooth_app/lib/pages/scan/scan_page_helper.dart b/packages/smooth_app/lib/pages/scan/scan_page_helper.dart
index 0393e55447f..8ee2aff9ee9 100644
--- a/packages/smooth_app/lib/pages/scan/scan_page_helper.dart
+++ b/packages/smooth_app/lib/pages/scan/scan_page_helper.dart
@@ -1,14 +1,8 @@
 import 'package:flutter/material.dart';
-import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 import 'package:provider/provider.dart';
 import 'package:smooth_app/data_models/continuous_scan_model.dart';
-import 'package:smooth_app/helpers/ui_helpers.dart';
 import 'package:smooth_app/pages/personalized_ranking_page.dart';
 import 'package:smooth_app/pages/product/common/product_query_page_helper.dart';
-import 'package:smooth_app/widgets/ranking_floating_action_button.dart';
-
-bool areButtonsRendered(ContinuousScanModel model) =>
-    model.hasMoreThanOneProduct;
 
 Future<void> openPersonalizedRankingPage(BuildContext context) async {
   final ContinuousScanModel model = context.read<ContinuousScanModel>();
@@ -27,45 +21,3 @@ Future<void> openPersonalizedRankingPage(BuildContext context) async {
   );
   await model.refresh();
 }
-
-Widget buildButtonsRow(BuildContext context, ContinuousScanModel model) {
-  final AppLocalizations appLocalizations = AppLocalizations.of(context)!;
-  final ButtonStyle buttonStyle = ButtonStyle(
-    shape: MaterialStateProperty.all<RoundedRectangleBorder>(
-      RoundedRectangleBorder(
-        borderRadius: BorderRadius.circular(18.0),
-      ),
-    ),
-  );
-  return AnimatedOpacity(
-    opacity: areButtonsRendered(model) ? 0.8 : 0.0,
-    duration: const Duration(milliseconds: 50),
-    child: Padding(
-      padding: const EdgeInsets.symmetric(
-        vertical: VERY_SMALL_SPACE,
-        horizontal: MEDIUM_SPACE,
-      ),
-      child: Row(
-        mainAxisAlignment: MainAxisAlignment.spaceBetween,
-        children: <Widget>[
-          ElevatedButton.icon(
-            style: buttonStyle,
-            icon: const Icon(Icons.cancel_outlined),
-            onPressed: model.clearScanSession,
-            label: Text(appLocalizations.clear),
-          ),
-          ElevatedButton.icon(
-            style: buttonStyle,
-            icon: const Icon(RankingFloatingActionButton.rankingIconData),
-            onPressed: () => openPersonalizedRankingPage(context),
-            label: Text(
-              appLocalizations.plural_compare_x_products(
-                model.getBarcodes().length,
-              ),
-            ),
-          ),
-        ],
-      ),
-    ),
-  );
-}
diff --git a/packages/smooth_app/lib/pages/scan/scanner_overlay.dart b/packages/smooth_app/lib/pages/scan/scanner_overlay.dart
index d1c6c6a0c33..cf8759454fa 100644
--- a/packages/smooth_app/lib/pages/scan/scanner_overlay.dart
+++ b/packages/smooth_app/lib/pages/scan/scanner_overlay.dart
@@ -1,8 +1,9 @@
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 import 'package:smooth_app/data_models/continuous_scan_model.dart';
 import 'package:smooth_app/generic_lib/animations/smooth_reveal_animation.dart';
 import 'package:smooth_app/generic_lib/widgets/smooth_view_finder.dart';
-import 'package:smooth_app/pages/scan/scan_page_helper.dart';
+import 'package:smooth_app/pages/scan/scan_header.dart';
 import 'package:smooth_app/widgets/smooth_product_carousel.dart';
 
 /// This builds all the essential widgets which are displayed above the camera
@@ -11,11 +12,9 @@ import 'package:smooth_app/widgets/smooth_product_carousel.dart';
 class ScannerOverlay extends StatelessWidget {
   const ScannerOverlay({
     required this.child,
-    required this.model,
   });
 
   final Widget child;
-  final ContinuousScanModel model;
 
   static const double carouselHeightPct = 0.55;
   static const double scannerWidthPct = 0.6;
@@ -24,6 +23,7 @@ class ScannerOverlay extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final ContinuousScanModel model = context.watch<ContinuousScanModel>();
     return LayoutBuilder(
       builder: (
         BuildContext context,
@@ -36,8 +36,9 @@ class ScannerOverlay extends StatelessWidget {
         );
         final double carouselHeight =
             constraints.maxHeight * ScannerOverlay.carouselHeightPct;
-        final double buttonRowHeight =
-            areButtonsRendered(model) ? ScannerOverlay.buttonRowHeightPx : 0;
+        final double buttonRowHeight = model.getBarcodes().isNotEmpty
+            ? ScannerOverlay.buttonRowHeightPx
+            : 0;
         final double availableScanHeight =
             constraints.maxHeight - carouselHeight - buttonRowHeight;
 
@@ -83,7 +84,7 @@ class ScannerOverlay extends StatelessWidget {
                 child: Column(
                   mainAxisAlignment: MainAxisAlignment.start,
                   children: <Widget>[
-                    SafeArea(top: true, child: buildButtonsRow(context, model)),
+                    const SafeArea(top: true, child: ScanHeader()),
                     const Spacer(),
                     SmoothProductCarousel(
                       showSearchCard: true,
diff --git a/packages/smooth_app/lib/pages/scan/search_page.dart b/packages/smooth_app/lib/pages/scan/search_page.dart
index b688226c070..e0b25fc3e24 100644
--- a/packages/smooth_app/lib/pages/scan/search_page.dart
+++ b/packages/smooth_app/lib/pages/scan/search_page.dart
@@ -5,6 +5,7 @@ import 'package:smooth_app/data_models/fetched_product.dart';
 import 'package:smooth_app/database/dao_string_list.dart';
 import 'package:smooth_app/database/keywords_product_query.dart';
 import 'package:smooth_app/database/local_database.dart';
+import 'package:smooth_app/helpers/analytics_helper.dart';
 import 'package:smooth_app/pages/product/common/product_dialog_helper.dart';
 import 'package:smooth_app/pages/product/common/product_query_page_helper.dart';
 import 'package:smooth_app/pages/product/new_product_page.dart';
@@ -46,6 +47,12 @@ Future<void> _onSubmittedBarcode(
   final FetchedProduct fetchedProduct =
       await productDialogHelper.openBestChoice();
   if (fetchedProduct.status == FetchedProductStatus.ok) {
+    AnalyticsHelper.trackSearch(
+      search: value,
+      searchCategory: 'barcode',
+      searchCount: 1,
+    );
+
     Navigator.push<Widget>(
       context,
       MaterialPageRoute<Widget>(
@@ -53,6 +60,11 @@ Future<void> _onSubmittedBarcode(
       ),
     );
   } else {
+    AnalyticsHelper.trackSearch(
+      search: value,
+      searchCategory: 'barcode',
+      searchCount: 0,
+    );
     productDialogHelper.openError(fetchedProduct);
   }
 }
diff --git a/packages/smooth_app/pubspec.lock b/packages/smooth_app/pubspec.lock
index 2689db18b0b..df758fc078e 100644
--- a/packages/smooth_app/pubspec.lock
+++ b/packages/smooth_app/pubspec.lock
@@ -232,13 +232,6 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.0"
-  fk_user_agent:
-    dependency: transitive
-    description:
-      name: fk_user_agent
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -518,13 +511,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.1.3"
-  matomo:
+  matomo_forever:
     dependency: "direct main"
     description:
-      name: matomo
+      name: matomo_forever
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.0.0+1"
   meta:
     dependency: transitive
     description:
@@ -957,13 +950,6 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.3.1"
-  universal_html:
-    dependency: transitive
-    description:
-      name: universal_html
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.0.8"
   universal_io:
     dependency: transitive
     description:
diff --git a/packages/smooth_app/pubspec.yaml b/packages/smooth_app/pubspec.yaml
index c94b3eaa5c1..a508d6a2d47 100644
--- a/packages/smooth_app/pubspec.yaml
+++ b/packages/smooth_app/pubspec.yaml
@@ -25,7 +25,7 @@ dependencies:
   image_picker: ^0.8.4+8
   iso_countries: 2.1.0
   latlong2: ^0.8.1
-  matomo: ^1.1.0
+  matomo_forever: ^1.0.0+1
   modal_bottom_sheet: ^2.0.0
   openfoodfacts: ^1.12.0
 #  openfoodfacts: