diff --git a/assets/js/pages/booking.js b/assets/js/pages/booking.js
index 7459e392..e9537bee 100644
--- a/assets/js/pages/booking.js
+++ b/assets/js/pages/booking.js
@@ -94,11 +94,11 @@ App.Pages.Booking = (function () {
         // Initialize page's components (tooltips, datepickers etc).
         tippy('[data-tippy-content]');
 
-        const weekDayId = App.Utils.Date.getWeekdayId(GlobalVariables.firstWeekday);
+        const weekdayId = App.Utils.Date.getWeekdayId(App.Vars.first_weekday);
 
         $selectDate.datepicker({
             dateFormat: 'dd-mm-yy',
-            firstDay: weekDayId,
+            firstDay: weekdayId,
             minDate: 0,
             defaultDate: moment().toDate(),
 
@@ -171,11 +171,7 @@ App.Pages.Booking = (function () {
 
         // If the manage mode is true, the appointments data should be loaded by default.
         if (manageMode) {
-            applyAppointmentData(
-                GlobalVariables.appointmentData,
-                GlobalVariables.providerData,
-                GlobalVariables.customerData
-            );
+            applyAppointmentData(App.Vars.appointment_data, App.Vars.provider_data, App.Vars.customer_data);
         } else {
             // Check if a specific service was selected (via URL parameter).
             const selectedServiceId = App.Utils.Url.queryParam('service');
@@ -191,8 +187,8 @@ App.Pages.Booking = (function () {
 
             if (selectedProviderId && $selectProvider.find('option[value="' + selectedProviderId + '"]').length === 0) {
                 // Select a service of this provider in order to make the provider available in the select box.
-                for (const index in GlobalVariables.availableProviders) {
-                    const provider = GlobalVariables.availableProviders[index];
+                for (const index in App.Vars.available_providers) {
+                    const provider = App.Vars.available_providers[index];
 
                     if (provider.id === selectedProviderId && provider.services.length > 0) {
                         $selectService.val(provider.services[0]).trigger('change');
@@ -253,7 +249,7 @@ App.Pages.Booking = (function () {
 
             $selectProvider.empty();
 
-            GlobalVariables.availableProviders.forEach((provider) => {
+            App.Vars.available_providers.forEach((provider) => {
                 // If the current provider is able to provide the selected service, add him to the list box.
                 const canServeService =
                     provider.services.filter((providerServiceId) => Number(providerServiceId) === Number(serviceId))
@@ -265,7 +261,7 @@ App.Pages.Booking = (function () {
             });
 
             // Add the "Any Provider" entry.
-            if ($selectProvider.find('option').length >= 1 && GlobalVariables.displayAnyProvider === '1') {
+            if ($selectProvider.find('option').length >= 1 && App.Vars.display_any_provider === '1') {
                 $selectProvider.prepend(new Option('- ' + App.Lang.any_provider + ' -', 'any-provider', true, true));
             }
 
@@ -457,7 +453,7 @@ App.Pages.Booking = (function () {
                     {
                         text: App.Lang.delete,
                         click: () => {
-                            App.Http.Booking.deletePersonalInformation(GlobalVariables.customerToken);
+                            App.Http.Booking.deletePersonalInformation(App.Vars.customer_token);
                         }
                     }
                 ];
@@ -487,7 +483,7 @@ App.Pages.Booking = (function () {
          * Event: Refresh captcha image.
          */
         $captchaTitle.on('click', 'button', () => {
-            $('.captcha-image').attr('src', GlobalVariables.baseUrl + '/index.php/captcha?' + Date.now());
+            $('.captcha-image').attr('src', App.Utils.Url.siteUrl('captcha?' + Date.now()));
         });
 
         $selectDate.on('mousedown', '.ui-datepicker-calendar td', () => {
@@ -693,10 +689,10 @@ App.Pages.Booking = (function () {
         data.manage_mode = manageMode;
 
         if (manageMode) {
-            data.appointment.id = GlobalVariables.appointmentData.id;
-            data.customer.id = GlobalVariables.customerData.id;
+            data.appointment.id = App.Vars.appointment_data.id;
+            data.customer.id = App.Vars.customer_data.id;
         }
-        $('input[name="csrfToken"]').val(GlobalVariables.csrfToken);
+        $('input[name="csrfToken"]').val(App.Vars.csrf_token);
         $('input[name="post_data"]').val(JSON.stringify(data));
     }
 
diff --git a/assets/js/pages/installation.js b/assets/js/pages/installation.js
index 55459b99..19d09e9d 100644
--- a/assets/js/pages/installation.js
+++ b/assets/js/pages/installation.js
@@ -162,7 +162,7 @@ App.Pages.Installation = (function () {
     }
 
     // Validate the base URL setting (must not contain any trailing slash).
-    if (GlobalVariables.baseUrl.slice(-1) === '/') {
+    if (App.Vars.base_url.slice(-1) === '/') {
         App.Utils.Message.show(
             'Invalid Configuration Detected',
             'Please remove any trailing slashes from your "BASE_URL" setting of the root "config.php" file and try again.'
diff --git a/assets/js/utils/calendar_table_view.js b/assets/js/utils/calendar_table_view.js
index 870d1c13..1459e1fd 100755
--- a/assets/js/utils/calendar_table_view.js
+++ b/assets/js/utils/calendar_table_view.js
@@ -159,8 +159,8 @@ App.Utils.CalendarTableView = (function () {
 
                             workingPlanExceptions[date] = workingPlanException;
 
-                            for (const index in GlobalVariables.availableProviders) {
-                                const availableProvider = GlobalVariables.availableProviders[index];
+                            for (const index in App.Vars.available_providers) {
+                                const availableProvider = App.Vars.available_providers[index];
 
                                 if (Number(availableProvider.id) === Number(provider.id)) {
                                     availableProvider.settings.working_plan_exceptions =
@@ -403,13 +403,13 @@ App.Utils.CalendarTableView = (function () {
             }
         });
 
-        const providers = GlobalVariables.availableProviders.filter(
+        const providers = App.Vars.available_providers.filter(
             (provider) =>
                 App.Vars.role_slug === App.Layouts.Backend.DB_SLUG_ADMIN ||
                 (App.Vars.role_slug === App.Layouts.Backend.DB_SLUG_SECRETARY &&
-                    GlobalVariables.secretaryProviders.indexOf(provider.id) !== -1) ||
+                    App.Vars.secretary_providers.indexOf(provider.id) !== -1) ||
                 (App.Vars.role_slug === App.Layouts.Backend.DB_SLUG_PROVIDER &&
-                    Number(provider.id) === Number(GlobalVariables.user.id))
+                    Number(provider.id) === Number(App.Vars.user_id))
         );
 
         // Create providers and service filters.
@@ -435,7 +435,7 @@ App.Utils.CalendarTableView = (function () {
             });
         } else {
             providers.forEach((provider) => {
-                if (Number(provider.id) === Number(GlobalVariables.user.id)) {
+                if (Number(provider.id) === Number(App.Vars.user_id)) {
                     $filterProvider.append(new Option(provider.first_name + ' ' + provider.last_name, provider.id));
                 }
             });
@@ -443,7 +443,7 @@ App.Utils.CalendarTableView = (function () {
 
         $filterProvider.select2();
 
-        const services = GlobalVariables.availableServices.filter((service) => {
+        const services = App.Vars.available_services.filter((service) => {
             const provider = providers.find((provider) => provider.services.indexOf(service.id) !== -1);
 
             return App.Vars.role_slug === App.Layouts.Backend.DB_SLUG_ADMIN || provider;
@@ -558,7 +558,7 @@ App.Utils.CalendarTableView = (function () {
         const filterProviderIds = $filterProvider.val();
         const filterServiceIds = $filterService.val();
 
-        let providers = GlobalVariables.availableProviders.filter((provider) => {
+        let providers = App.Vars.available_providers.filter((provider) => {
             const servedServiceIds = provider.services.filter((serviceId) => {
                 const matches = filterServiceIds.filter(
                     (filterServiceId) => Number(serviceId) === Number(filterServiceId)
@@ -581,8 +581,8 @@ App.Utils.CalendarTableView = (function () {
         });
 
         if (App.Vars.role_slug === 'provider') {
-            GlobalVariables.availableProviders.forEach((provider) => {
-                if (Number(provider.id) === Number(GlobalVariables.user.id)) {
+            App.Vars.available_providers.forEach((provider) => {
+                if (Number(provider.id) === Number(App.Vars.user_id)) {
                     providers = [provider];
                 }
             });
@@ -590,8 +590,8 @@ App.Utils.CalendarTableView = (function () {
 
         if (App.Vars.role_slug === 'secretary') {
             providers = [];
-            GlobalVariables.availableProviders.forEach((provider) => {
-                if (GlobalVariables.secretaryProviders.indexOf(provider.id) > -1) {
+            App.Vars.available_providers.forEach((provider) => {
+                if (App.Vars.secretary_providers.indexOf(provider.id) > -1) {
                     providers.push(provider);
                 }
             });
@@ -674,7 +674,7 @@ App.Utils.CalendarTableView = (function () {
         let timeFormat = '';
         let slotTimeFormat = '';
 
-        switch (GlobalVariables.timeFormat) {
+        switch (App.Vars.time_format) {
             case 'military':
                 timeFormat = 'H:mm';
                 slotTimeFormat = 'H(:mm)';
@@ -684,7 +684,7 @@ App.Utils.CalendarTableView = (function () {
                 slotTimeFormat = 'h(:mm) a';
                 break;
             default:
-                throw new Error('Invalid time format setting provided!' + GlobalVariables.timeFormat);
+                throw new Error('Invalid time format setting provided!' + App.Vars.time_format);
         }
 
         const firstWeekday = App.Vars.first_weekday;
@@ -719,11 +719,11 @@ App.Utils.CalendarTableView = (function () {
                 const $providerColumn = $(jsEvent.target).parents('.provider-column');
                 const providerId = $providerColumn.data('provider').id;
 
-                const provider = GlobalVariables.availableProviders.find(
+                const provider = App.Vars.available_providers.find(
                     (provider) => Number(provider.id) === Number(providerId)
                 );
 
-                const service = GlobalVariables.availableServices.find(
+                const service = App.Vars.available_services.find(
                     (service) => provider.services.indexOf(service.id) !== -1
                 );
 
diff --git a/assets/js/utils/general_functions.js b/assets/js/utils/general_functions.js
index 634178e5..6b167e2d 100755
--- a/assets/js/utils/general_functions.js
+++ b/assets/js/utils/general_functions.js
@@ -289,10 +289,10 @@ window.GeneralFunctions = window.GeneralFunctions || {};
 
         $(document).on('click', 'li.language', function () {
             // Change language with ajax call and refresh page.
-            var url = GlobalVariables.baseUrl + '/index.php/backend_api/ajax_change_language';
+            var url = App.Vars.base_url + '/index.php/backend_api/ajax_change_language';
 
             var data = {
-                csrf_token: GlobalVariables.csrfToken,
+                csrf_token: App.Vars.csrf_token,
                 language: $(this).attr('data-language')
             };
 
@@ -362,7 +362,7 @@ window.GeneralFunctions = window.GeneralFunctions || {};
      * @return {String} Returns the formatted date string.
      */
     exports.formatDate = function (date, dateFormatSetting, addHours) {
-        var timeFormat = GlobalVariables.timeFormat === 'regular' ? 'h:mm a' : 'HH:mm';
+        var timeFormat = App.Vars.time_format === 'regular' ? 'h:mm a' : 'HH:mm';
         var hours = addHours ? ' ' + timeFormat : '';
         var result;
         var parsedDateMoment = moment(date);