diff --git a/src/addon/calendar/providers/calendar.ts b/src/addon/calendar/providers/calendar.ts
index 886a21670..d5a9a89fc 100644
--- a/src/addon/calendar/providers/calendar.ts
+++ b/src/addon/calendar/providers/calendar.ts
@@ -230,8 +230,8 @@ export class AddonCalendarProvider {
 
                 return this.groupsProvider.getUserGroups(courses, siteId).then((groups) => {
                     let now = this.timeUtils.timestamp(),
-                        start = now + (CoreConstants.secondsDay * daysToStart),
-                        end = start + (CoreConstants.secondsDay * daysInterval);
+                        start = now + (CoreConstants.SECONDS_DAY * daysToStart),
+                        end = start + (CoreConstants.SECONDS_DAY * daysInterval);
 
                     // The core_calendar_get_calendar_events needs all the current user courses and groups.
                     let data = {
diff --git a/src/classes/site.ts b/src/classes/site.ts
index 261887d74..3b730ea47 100644
--- a/src/classes/site.ts
+++ b/src/classes/site.ts
@@ -435,7 +435,7 @@ export class CoreSite {
         // Check if the method is available, use a prefixed version if possible.
         // We ignore this check when we do not have the site info, as the list of functions is not loaded yet.
         if (this.getInfo() && !this.wsAvailable(method, false)) {
-            const compatibilityMethod = CoreConstants.wsPrefix + method;
+            const compatibilityMethod = CoreConstants.WS_PREFIX + method;
             if (this.wsAvailable(compatibilityMethod, false)) {
                 this.logger.info(`Using compatibility WS method '${compatibilityMethod}'`);
                 method = compatibilityMethod;
@@ -565,7 +565,7 @@ export class CoreSite {
 
         // Let's try again with the compatibility prefix.
         if (checkPrefix) {
-            return this.wsAvailable(CoreConstants.wsPrefix + method, false);
+            return this.wsAvailable(CoreConstants.WS_PREFIX + method, false);
         }
 
         return false;
@@ -877,7 +877,7 @@ export class CoreSite {
             return Promise.resolve({code: 0});
         }
 
-        let observable = this.http.post(checkUrl, {service: service}).timeout(CoreConstants.wsTimeout);
+        let observable = this.http.post(checkUrl, {service: service}).timeout(CoreConstants.WS_TIMEOUT);
         return this.utils.observableToPromise(observable).then((data: any) => {
             if (typeof data != 'undefined' && data.errorcode === 'requirecorrectaccess') {
                 if (!retrying) {
@@ -930,7 +930,7 @@ export class CoreSite {
         }
 
         this.infos.functions.forEach((func) => {
-            if (func.name.indexOf(CoreConstants.wsPrefix) != -1) {
+            if (func.name.indexOf(CoreConstants.WS_PREFIX) != -1) {
                 appUsesLocalMobile = true;
             }
         });
@@ -1074,7 +1074,7 @@ export class CoreSite {
         };
 
         if (!this.privateToken || !this.wsAvailable('tool_mobile_get_autologin_key') ||
-                (this.lastAutoLogin && this.timeUtils.timestamp() - this.lastAutoLogin < 6 * CoreConstants.secondsMinute)) {
+                (this.lastAutoLogin && this.timeUtils.timestamp() - this.lastAutoLogin < 6 * CoreConstants.SECONDS_MINUTE)) {
             // No private token, WS not available or last auto-login was less than 6 minutes ago.
             // Open the final URL without auto-login.
             return Promise.resolve(open(url));
diff --git a/src/components/file/file.ts b/src/components/file/file.ts
index 0506bea4f..4c33517d8 100644
--- a/src/components/file/file.ts
+++ b/src/components/file/file.ts
@@ -102,10 +102,10 @@ export class CoreFileComponent implements OnInit, OnDestroy {
         return this.filepoolProvider.getFileStateByUrl(this.siteId, this.fileUrl, this.timemodified).then((state) => {
             let canDownload = this.sitesProvider.getCurrentSite().canDownloadFiles();
 
-            this.isDownloaded = state === CoreConstants.downloaded || state === CoreConstants.outdated;
-            this.isDownloading = canDownload && state === CoreConstants.downloading;
-            this.showDownload = canDownload && (state === CoreConstants.notDownloaded || state === CoreConstants.outdated ||
-                    (this.alwaysDownload && state === CoreConstants.downloaded));
+            this.isDownloaded = state === CoreConstants.DOWNLOADED || state === CoreConstants.OUTDATED;
+            this.isDownloading = canDownload && state === CoreConstants.DOWNLOADING;
+            this.showDownload = canDownload && (state === CoreConstants.NOT_DOWNLOADED || state === CoreConstants.OUTDATED ||
+                    (this.alwaysDownload && state === CoreConstants.DOWNLOADED));
         });
     }
 
@@ -207,7 +207,7 @@ export class CoreFileComponent implements OnInit, OnDestroy {
 
                     let subPromise;
 
-                    if (status === CoreConstants.notDownloaded) {
+                    if (status === CoreConstants.NOT_DOWNLOADED) {
                         // File is not downloaded, download and then return the local URL.
                         subPromise = this.downloadFile();
                     } else {
diff --git a/src/core/constants.ts b/src/core/constants.ts
index 524cc86ec..519460a68 100644
--- a/src/core/constants.ts
+++ b/src/core/constants.ts
@@ -16,34 +16,34 @@
  * Static class to contain all the core constants.
  */
 export class CoreConstants {
-    public static secondsYear = 31536000;
-    public static secondsWeek = 604800;
-    public static secondsDay = 86400;
-    public static secondsHour = 3600;
-    public static secondsMinute = 60;
-    public static wifiDownloadThreshold = 104857600; // 100MB.
-    public static downloadThreshold = 10485760; // 10MB.
-    public static dontShowError = 'CoreDontShowError';
-    public static noSiteId = 'NoSite';
+    public static SECONDS_YEAR = 31536000;
+    public static SECONDS_WEEK = 604800;
+    public static SECONDS_DAY = 86400;
+    public static SECONDS_HOUR = 3600;
+    public static SECONDS_MINUTE = 60;
+    public static WIFI_DOWNLOAD_THRESHOLD = 104857600; // 100MB.
+    public static DOWNLOAD_THRESHOLD = 10485760; // 10MB.
+    public static DONT_SHOW_ERROR = 'CoreDontShowError';
+    public static NO_SITE_ID = 'NoSite';
 
     // Settings constants.
-    public static settingsRichTextEditor = 'CoreSettingsRichTextEditor';
-    public static settingsNotificationSound = 'CoreSettingsNotificationSound';
-    public static settingsSyncOnlyOnWifi = 'mmCoreSyncOnlyOnWifi';
+    public static SETTINGS_RICH_TEXT_EDITOR = 'CoreSettingsRichTextEditor';
+    public static SETTINGS_NOTIFICATION_SOUND = 'CoreSettingsNotificationSound';
+    public static SETTINGS_SYNC_ONLY_ON_WIFI = 'CoreSettingsSyncOnlyOnWifi';
 
     // WS constants.
-    public static wsTimeout = 30000;
-    public static wsPrefix = 'local_mobile_';
+    public static WS_TIMEOUT = 30000;
+    public static WS_PREFIX = 'local_mobile_';
 
     // Login constants.
-    public static loginSSOCode = 2; // SSO in browser window is required.
-    public static loginSSOInAppCode = 3; // SSO in embedded browser is required.
-    public static loginLaunchData = 'mmLoginLaunchData';
+    public static LOGIN_SSO_CODE = 2; // SSO in browser window is required.
+    public static LOGIN_SSO_INAPP_CODE = 3; // SSO in embedded browser is required.
+    public static LOGIN_LAUNCH_DATA = 'CoreLoginLaunchData';
 
     // Download status constants.
-    public static downloaded = 'downloaded';
-    public static downloading = 'downloading';
-    public static notDownloaded = 'notdownloaded';
-    public static outdated = 'outdated';
-    public static notDownloadable = 'notdownloadable';
+    public static DOWNLOADED = 'downloaded';
+    public static DOWNLOADING = 'downloading';
+    public static NOT_DOWNLOADED = 'notdownloaded';
+    public static OUTDATED = 'outdated';
+    public static NOT_DOWNLOADABLE = 'notdownloadable';
 }
diff --git a/src/core/course/formats/weeks/providers/handler.ts b/src/core/course/formats/weeks/providers/handler.ts
index 3405f9721..b6f5beff7 100644
--- a/src/core/course/formats/weeks/providers/handler.ts
+++ b/src/core/course/formats/weeks/providers/handler.ts
@@ -78,10 +78,10 @@ export class CoreCourseFormatWeeksHandler implements CoreCourseFormatHandler {
         startDate = startDate + 7200;
 
         let dates = {
-            start: startDate + (CoreConstants.secondsWeek * (section.section - 1)),
+            start: startDate + (CoreConstants.SECONDS_WEEK * (section.section - 1)),
             end: 0
         };
-        dates.end = dates.start + CoreConstants.secondsWeek;
+        dates.end = dates.start + CoreConstants.SECONDS_WEEK;
         return dates;
     }
 }
diff --git a/src/core/course/providers/course.ts b/src/core/course/providers/course.ts
index 1323b9ef9..4c4300cc9 100644
--- a/src/core/course/providers/course.ts
+++ b/src/core/course/providers/course.ts
@@ -28,6 +28,7 @@ import { CoreConstants } from '../../constants';
 @Injectable()
 export class CoreCourseProvider {
     public static ALL_SECTIONS_ID = -1;
+    protected ROOT_CACHE_KEY = 'mmCourse:';
 
     // Variables for database.
     protected COURSE_STATUS_TABLE = 'course_status';
@@ -64,7 +65,7 @@ export class CoreCourseProvider {
     }
 
     protected logger;
-    protected coreModules = [
+    protected CORE_MODULES = [
         'assign', 'assignment', 'book', 'chat', 'choice', 'data', 'database', 'date', 'external-tool',
         'feedback', 'file', 'folder', 'forum', 'glossary', 'ims', 'imscp', 'label', 'lesson', 'lti', 'page', 'quiz',
         'resource', 'scorm', 'survey', 'url', 'wiki', 'workshop'
@@ -103,7 +104,7 @@ export class CoreCourseProvider {
             this.logger.debug('Clear all course status for site ' + site.id);
 
             return site.getDb().deleteRecords(this.COURSE_STATUS_TABLE).then(() => {
-                this.triggerCourseStatusChanged(-1, CoreConstants.notDownloaded, site.id);
+                this.triggerCourseStatusChanged(-1, CoreConstants.NOT_DOWNLOADED, site.id);
             });
         });
     }
@@ -147,7 +148,7 @@ export class CoreCourseProvider {
      * @return {string} Cache key.
      */
     protected getActivitiesCompletionCacheKey(courseId: number, userId: number) : string {
-        return this.getRootCacheKey() + 'activitiescompletion:' + courseId + ':' + userId;
+        return this.ROOT_CACHE_KEY + 'activitiescompletion:' + courseId + ':' + userId;
     }
 
     /**
@@ -177,9 +178,9 @@ export class CoreCourseProvider {
      */
     getCourseStatus(courseId: number, siteId?: string) : Promise<string> {
         return this.getCourseStatusData(courseId, siteId).then((entry) => {
-            return entry.status || CoreConstants.notDownloaded;
+            return entry.status || CoreConstants.NOT_DOWNLOADED;
         }).catch(() => {
-            return CoreConstants.notDownloaded;
+            return CoreConstants.NOT_DOWNLOADED;
         });
     }
 
@@ -352,7 +353,7 @@ export class CoreCourseProvider {
      * @return {string} Cache key.
      */
     protected getModuleBasicInfoByInstanceCacheKey(id: number, module: string) : string {
-        return this.getRootCacheKey() + 'moduleByInstance:' + module + ':' + id;
+        return this.ROOT_CACHE_KEY + 'moduleByInstance:' + module + ':' + id;
     }
 
     /**
@@ -362,7 +363,7 @@ export class CoreCourseProvider {
      * @return {string} Cache key.
      */
     protected getModuleCacheKey(moduleId: number) : string {
-        return this.getRootCacheKey() + 'module:' + moduleId;
+        return this.ROOT_CACHE_KEY + 'module:' + moduleId;
     }
 
     /**
@@ -372,7 +373,7 @@ export class CoreCourseProvider {
      * @return {string} The IMG src.
      */
     getModuleIconSrc(moduleName: string) : string {
-        if (this.coreModules.indexOf(moduleName) < 0) {
+        if (this.CORE_MODULES.indexOf(moduleName) < 0) {
             moduleName = 'external-tool';
         }
 
@@ -393,15 +394,6 @@ export class CoreCourseProvider {
         });
     }
 
-    /**
-     * Get the root cache key for the WS calls related to courses.
-     *
-     * @return {string} Root cache key.
-     */
-    protected getRootCacheKey() : string {
-        return 'mmCourse:';
-    }
-
     /**
      * Return a specific section.
      *
@@ -487,7 +479,7 @@ export class CoreCourseProvider {
      * @return {string} Cache key.
      */
     protected getSectionsCacheKey(courseId) : string {
-        return this.getRootCacheKey() + 'sections:' + courseId;
+        return this.ROOT_CACHE_KEY + 'sections:' + courseId;
     }
 
     /**
@@ -609,9 +601,9 @@ export class CoreCourseProvider {
             return this.getCourseStatusData(courseId, siteId).then((entry) => {
                 this.logger.debug(`Set previous status '${entry.status}' for course ${courseId}`);
 
-                newData.status = entry.previous || CoreConstants.notDownloaded;
+                newData.status = entry.previous || CoreConstants.NOT_DOWNLOADED;
                 newData.updated = Date.now();
-                if (entry.status == CoreConstants.downloading) {
+                if (entry.status == CoreConstants.DOWNLOADING) {
                     // Going back from downloading to previous status, restore previous download time.
                     newData.downloadTime = entry.previousDownloadTime;
                 }
@@ -642,7 +634,7 @@ export class CoreCourseProvider {
             let downloadTime,
                 previousDownloadTime;
 
-            if (status == CoreConstants.downloading) {
+            if (status == CoreConstants.DOWNLOADING) {
                 // Set download time if course is now downloading.
                 downloadTime = this.timeUtils.timestamp();
             }
@@ -689,7 +681,7 @@ export class CoreCourseProvider {
      * @return {string} Translated name.
      */
     translateModuleName(moduleName: string) : string {
-        if (this.coreModules.indexOf(moduleName) < 0) {
+        if (this.CORE_MODULES.indexOf(moduleName) < 0) {
             moduleName = 'external-tool';
         }
 
diff --git a/src/core/courses/providers/courses.ts b/src/core/courses/providers/courses.ts
index 9e8e0623b..ebb15e8d8 100644
--- a/src/core/courses/providers/courses.ts
+++ b/src/core/courses/providers/courses.ts
@@ -28,6 +28,7 @@ export class CoreCoursesProvider {
     public static EVENT_MY_COURSES_REFRESHED = 'courses_my_courses_refreshed';
     public static ACCESS_GUEST = 'courses_access_guest';
     public static ACCESS_DEFAULT = 'courses_access_default';
+    protected ROOT_CACHE_KEY = 'mmCourses:';
     protected logger;
 
     constructor(logger: CoreLoggerProvider, private sitesProvider: CoreSitesProvider) {
@@ -68,7 +69,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getCategoriesCacheKey(categoryId: number, addSubcategories?: boolean) : string {
-        return this.getRootCacheKey() + 'categories:' + categoryId + ':' + !!addSubcategories;
+        return this.ROOT_CACHE_KEY + 'categories:' + categoryId + ':' + !!addSubcategories;
     }
 
     /**
@@ -121,15 +122,6 @@ export class CoreCoursesProvider {
         });
     }
 
-    /**
-     * Get the root cache key for the WS calls related to courses.
-     *
-     * @return {string} Root cache key.
-     */
-    protected getRootCacheKey() : string {
-        return 'mmCourses:';
-    }
-
     /**
      * Check if My Courses is disabled in a certain site.
      *
@@ -219,7 +211,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getCourseEnrolmentMethodsCacheKey(id: number) : string {
-        return this.getRootCacheKey() + 'enrolmentmethods:' + id;
+        return this.ROOT_CACHE_KEY + 'enrolmentmethods:' + id;
     }
 
     /**
@@ -251,7 +243,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getCourseGuestEnrolmentInfoCacheKey(instanceId: number) : string {
-        return this.getRootCacheKey() + 'guestinfo:' + instanceId;
+        return this.ROOT_CACHE_KEY + 'guestinfo:' + instanceId;
     }
 
     /**
@@ -291,7 +283,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getCoursesCacheKey(ids: number[]) : string {
-        return this.getRootCacheKey() + 'course:' + JSON.stringify(ids);
+        return this.ROOT_CACHE_KEY + 'course:' + JSON.stringify(ids);
     }
 
     /**
@@ -352,7 +344,7 @@ export class CoreCoursesProvider {
     protected getCoursesByFieldCacheKey(field?: string, value?: any) : string {
         field = field || '';
         value = field ? value : '';
-        return this.getRootCacheKey() + 'coursesbyfield:' + field + ':' + value;
+        return this.ROOT_CACHE_KEY + 'coursesbyfield:' + field + ':' + value;
     }
 
     /**
@@ -408,7 +400,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getUserAdministrationOptionsCommonCacheKey() : string {
-        return this.getRootCacheKey() + 'administrationOptions:';
+        return this.ROOT_CACHE_KEY + 'administrationOptions:';
     }
 
     /**
@@ -451,7 +443,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getUserNavigationOptionsCommonCacheKey() : string {
-        return this.getRootCacheKey() + 'navigationOptions:';
+        return this.ROOT_CACHE_KEY + 'navigationOptions:';
     }
 
     /**
@@ -566,7 +558,7 @@ export class CoreCoursesProvider {
      * @return {string} Cache key.
      */
     protected getUserCoursesCacheKey() : string {
-        return this.getRootCacheKey() + 'usercourses';
+        return this.ROOT_CACHE_KEY + 'usercourses';
     }
 
     /**
diff --git a/src/core/courses/providers/my-overview.ts b/src/core/courses/providers/my-overview.ts
index aab67f913..a6b785fde 100644
--- a/src/core/courses/providers/my-overview.ts
+++ b/src/core/courses/providers/my-overview.ts
@@ -24,6 +24,7 @@ import * as moment from 'moment';
 export class CoreCoursesMyOverviewProvider {
     public static EVENTS_LIMIT = 20;
     public static EVENTS_LIMIT_PER_COURSE = 10;
+    protected ROOT_CACHE_KEY = 'myoverview:';
 
     constructor(private sitesProvider: CoreSitesProvider) {}
 
@@ -113,7 +114,7 @@ export class CoreCoursesMyOverviewProvider {
      * @return {string} Cache key.
      */
     protected getActionEventsByCoursesCacheKey() : string {
-        return this.getRootCacheKey() + 'bycourse';
+        return this.ROOT_CACHE_KEY + 'bycourse';
     }
 
     /**
@@ -165,7 +166,7 @@ export class CoreCoursesMyOverviewProvider {
      * @return {string} Cache key.
      */
     protected getActionEventsByTimesortPrefixCacheKey() : string {
-        return this.getRootCacheKey() + 'bytimesort:';
+        return this.ROOT_CACHE_KEY + 'bytimesort:';
     }
 
     /**
@@ -181,15 +182,6 @@ export class CoreCoursesMyOverviewProvider {
         return this.getActionEventsByTimesortPrefixCacheKey() + afterEventId + ':' + limit;
     }
 
-    /**
-     * Get the root cache key for the WS calls related to overview.
-     *
-     * @return {string} Root cache key.
-     */
-    protected getRootCacheKey() : string {
-        return 'myoverview:';
-    }
-
     /**
      * Invalidates get calendar action events for a given list of courses WS call.
      *
diff --git a/src/core/emulator/pages/capture-media/capture-media.ts b/src/core/emulator/pages/capture-media/capture-media.ts
index e94d15be5..353648b3e 100644
--- a/src/core/emulator/pages/capture-media/capture-media.ts
+++ b/src/core/emulator/pages/capture-media/capture-media.ts
@@ -354,7 +354,7 @@ export class CoreEmulatorCaptureMediaPage implements OnInit, OnDestroy {
 
         // Create the file and return it.
         let fileName = this.type + '_' + this.timeUtils.readableTimestamp() + '.' + this.extension,
-            path = this.textUtils.concatenatePaths(this.fileProvider.TMPFOLDER, 'media/' + fileName);
+            path = this.textUtils.concatenatePaths(CoreFileProvider.TMPFOLDER, 'media/' + fileName);
 
         let loadingModal = this.domUtils.showModalLoading();
 
diff --git a/src/core/emulator/providers/local-notifications.ts b/src/core/emulator/providers/local-notifications.ts
index d7eef13db..2d8e27af1 100644
--- a/src/core/emulator/providers/local-notifications.ts
+++ b/src/core/emulator/providers/local-notifications.ts
@@ -466,7 +466,7 @@ export class LocalNotificationsMock extends LocalNotifications {
                     // Schedule the notification again unless it should have been triggered more than an hour ago.
                     delete notification.triggered;
                     notification.at = notification.at * 1000;
-                    if (notification.at - Date.now() > - CoreConstants.secondsHour * 1000) {
+                    if (notification.at - Date.now() > - CoreConstants.SECONDS_HOUR * 1000) {
                         this.schedule(notification);
                     }
                 }
@@ -551,19 +551,19 @@ export class LocalNotificationsMock extends LocalNotifications {
         } else if (every == 'second') {
             interval = 1000;
         } else if (every == 'minute') {
-            interval = CoreConstants.secondsMinute * 1000;
+            interval = CoreConstants.SECONDS_MINUTE * 1000;
         } else if (every == 'hour') {
-            interval = CoreConstants.secondsHour * 1000;
+            interval = CoreConstants.SECONDS_HOUR * 1000;
         } else if (every == 'day') {
-            interval = CoreConstants.secondsDay * 1000;
+            interval = CoreConstants.SECONDS_DAY * 1000;
         } else if (every == 'week') {
-            interval = CoreConstants.secondsDay * 7 * 1000;
+            interval = CoreConstants.SECONDS_DAY * 7 * 1000;
         } else if (every == 'month') {
-            interval = CoreConstants.secondsDay * 31 * 1000;
+            interval = CoreConstants.SECONDS_DAY * 31 * 1000;
         } else if (every == 'quarter') {
-            interval = CoreConstants.secondsHour * 2190 * 1000;
+            interval = CoreConstants.SECONDS_HOUR * 2190 * 1000;
         } else if (every == 'year') {
-            interval = CoreConstants.secondsYear * 1000;
+            interval = CoreConstants.SECONDS_YEAR * 1000;
         } else {
             interval = parseInt(every, 10);
             if (isNaN(interval)) {
@@ -713,7 +713,7 @@ export class LocalNotificationsMock extends LocalNotifications {
                     tag: notification.id + '',
                     template: this.tileTemplate,
                     strings: [notification.title, notification.text, notification.title,  notification.text, notification.title, notification.text],
-                    expirationTime: new Date(Date.now() + CoreConstants.secondsHour * 1000) // Expire in 1 hour.
+                    expirationTime: new Date(Date.now() + CoreConstants.SECONDS_HOUR * 1000) // Expire in 1 hour.
                 })
 
                 tileNotif.show()
diff --git a/src/core/fileuploader/providers/helper.ts b/src/core/fileuploader/providers/helper.ts
index 07936bb1d..438ee93c9 100644
--- a/src/core/fileuploader/providers/helper.ts
+++ b/src/core/fileuploader/providers/helper.ts
@@ -94,13 +94,13 @@ export class CoreFileUploaderHelperProvider {
             fileData;
 
         // We have the data of the file to be uploaded, but not its URL (needed). Create a copy of the file to upload it.
-        return this.fileProvider.readFileData(file, this.fileProvider.FORMATARRAYBUFFER).then((data) => {
+        return this.fileProvider.readFileData(file, CoreFileProvider.FORMATARRAYBUFFER).then((data) => {
             fileData = data;
 
             // Get unique name for the copy.
-            return this.fileProvider.getUniqueNameInFolder(this.fileProvider.TMPFOLDER, name);
+            return this.fileProvider.getUniqueNameInFolder(CoreFileProvider.TMPFOLDER, name);
         }).then((newName) => {
-            let filePath = this.textUtils.concatenatePaths(this.fileProvider.TMPFOLDER, newName);
+            let filePath = this.textUtils.concatenatePaths(CoreFileProvider.TMPFOLDER, newName);
 
             return this.fileProvider.writeFile(filePath, fileData);
         }).catch((error) => {
@@ -158,10 +158,10 @@ export class CoreFileUploaderHelperProvider {
             fileName = fileName.replace(/(\.[^\.]*)\?[^\.]*$/, '$1');
 
             // Get a unique name in the folder to prevent overriding another file.
-            return this.fileProvider.getUniqueNameInFolder(this.fileProvider.TMPFOLDER, fileName, defaultExt);
+            return this.fileProvider.getUniqueNameInFolder(CoreFileProvider.TMPFOLDER, fileName, defaultExt);
         }).then((newName) => {
             // Now move or copy the file.
-            const destPath = this.textUtils.concatenatePaths(this.fileProvider.TMPFOLDER, newName);
+            const destPath = this.textUtils.concatenatePaths(CoreFileProvider.TMPFOLDER, newName);
             if (shouldDelete) {
                 return this.fileProvider.moveExternalFile(path, destPath);
             } else {
diff --git a/src/core/login/pages/init/init.ts b/src/core/login/pages/init/init.ts
index 7be53c668..7926f43f1 100644
--- a/src/core/login/pages/init/init.ts
+++ b/src/core/login/pages/init/init.ts
@@ -47,7 +47,7 @@ export class CoreLoginInitPage {
 
                 // Only accept the redirect if it was stored less than 20 seconds ago.
                 if (Date.now() - redirectData.timemodified < 20000) {
-                    if (redirectData.siteId != CoreConstants.noSiteId) {
+                    if (redirectData.siteId != CoreConstants.NO_SITE_ID) {
                         // The redirect is pointing to a site, load it.
                         return this.sitesProvider.loadSite(redirectData.siteId).then(() => {
                             if (!this.loginHelper.isSiteLoggedOut(redirectData.page, redirectData.params)) {
diff --git a/src/core/login/providers/helper.ts b/src/core/login/providers/helper.ts
index 08caa097c..8f21a8a52 100644
--- a/src/core/login/providers/helper.ts
+++ b/src/core/login/providers/helper.ts
@@ -187,7 +187,7 @@ export class CoreLoginHelperProvider {
      * Show a confirm modal if needed and open a browser to perform SSO login.
      *
      * @param  {string} siteurl     URL of the site where the SSO login will be performed.
-     * @param  {number} typeOfLogin CoreConstants.loginSSOCode or CoreConstants.loginSSOInAppCode.
+     * @param  {number} typeOfLogin CoreConstants.LOGIN_SSO_CODE or CoreConstants.LOGIN_SSO_INAPP_CODE.
      * @param  {string} [service]   The service to use. If not defined, external service will be used.
      * @param  {string} [launchUrl] The URL to open for SSO. If not defined, local_mobile launch URL will be used.
      * @return {Void}
@@ -594,7 +594,7 @@ export class CoreLoginHelperProvider {
             return true;
         }
 
-        return code == CoreConstants.loginSSOInAppCode;
+        return code == CoreConstants.LOGIN_SSO_INAPP_CODE;
     }
 
     /**
@@ -604,7 +604,7 @@ export class CoreLoginHelperProvider {
      * @return {boolean} True if SSO login is needed, false othwerise.
      */
     isSSOLoginNeeded(code: number) : boolean {
-        return code == CoreConstants.loginSSOCode || code == CoreConstants.loginSSOInAppCode;
+        return code == CoreConstants.LOGIN_SSO_CODE || code == CoreConstants.LOGIN_SSO_INAPP_CODE;
     }
 
     /**
@@ -615,7 +615,7 @@ export class CoreLoginHelperProvider {
      * @param {string} siteId Site to load.
      */
     protected loadSiteAndPage(page: string, params: any, siteId: string) : void {
-        if (siteId == CoreConstants.noSiteId) {
+        if (siteId == CoreConstants.NO_SITE_ID) {
             // Page doesn't belong to a site, just load the page.
             this.appProvider.getRootNavController().setRoot(page, params);
         } else {
@@ -687,7 +687,7 @@ export class CoreLoginHelperProvider {
      * Open a browser to perform SSO login.
      *
      * @param {string} siteurl URL of the site where the SSO login will be performed.
-     * @param {number} typeOfLogin CoreConstants.loginSSOCode or CoreConstants.loginSSOInAppCode.
+     * @param {number} typeOfLogin CoreConstants.LOGIN_SSO_CODE or CoreConstants.LOGIN_SSO_INAPP_CODE.
      * @param {string} [service] The service to use. If not defined, external service will be used.
      * @param {string} [launchUrl] The URL to open for SSO. If not defined, local_mobile launch URL will be used.
      * @param {string} [pageName] Name of the page to go once authenticated. If not defined, site initial page.
@@ -791,7 +791,7 @@ export class CoreLoginHelperProvider {
 
         // Store the siteurl and passport in $mmConfig for persistence. We are "configuring"
         // the app to wait for an SSO. $mmConfig shouldn't be used as a temporary storage.
-        this.configProvider.set(CoreConstants.loginLaunchData, JSON.stringify({
+        this.configProvider.set(CoreConstants.LOGIN_LAUNCH_DATA, JSON.stringify({
             siteUrl: siteUrl,
             passport: passport,
             pageName: pageName || '',
@@ -934,7 +934,7 @@ export class CoreLoginHelperProvider {
     /**
      * Check if a confirm should be shown to open a SSO authentication.
      *
-     * @param {number} typeOfLogin CoreConstants.loginSSOCode or CoreConstants.loginSSOInAppCode.
+     * @param {number} typeOfLogin CoreConstants.LOGIN_SSO_CODE or CoreConstants.LOGIN_SSO_INAPP_CODE.
      * @return {boolean} True if confirm modal should be shown, false otherwise.
      */
     shouldShowSSOConfirm(typeOfLogin: number) : boolean {
@@ -988,7 +988,7 @@ export class CoreLoginHelperProvider {
         // Split signature:::token
         const params = url.split(":::");
 
-        return this.configProvider.get(CoreConstants.loginLaunchData).then((data): any => {
+        return this.configProvider.get(CoreConstants.LOGIN_LAUNCH_DATA).then((data): any => {
             try {
                 data = JSON.parse(data);
             } catch(ex) {
@@ -999,7 +999,7 @@ export class CoreLoginHelperProvider {
                 passport = data.passport;
 
             // Reset temporary values.
-            this.configProvider.delete(CoreConstants.loginLaunchData);
+            this.configProvider.delete(CoreConstants.LOGIN_LAUNCH_DATA);
 
             // Validate the signature.
             // We need to check both http and https.
diff --git a/src/pipes/seconds-to-hms.ts b/src/pipes/seconds-to-hms.ts
index 8160522a2..34bd4d3cf 100644
--- a/src/pipes/seconds-to-hms.ts
+++ b/src/pipes/seconds-to-hms.ts
@@ -57,10 +57,10 @@ export class CoreSecondsToHMSPipe implements PipeTransform {
         // Don't allow decimals.
         seconds = Math.floor(seconds);
 
-        hours = Math.floor(seconds / CoreConstants.secondsHour);
-        seconds -= hours * CoreConstants.secondsHour;
-        minutes = Math.floor(seconds / CoreConstants.secondsMinute);
-        seconds -= minutes * CoreConstants.secondsMinute;
+        hours = Math.floor(seconds / CoreConstants.SECONDS_HOUR);
+        seconds -= hours * CoreConstants.SECONDS_HOUR;
+        minutes = Math.floor(seconds / CoreConstants.SECONDS_MINUTE);
+        seconds -= minutes * CoreConstants.SECONDS_MINUTE;
 
         return this.textUtils.twoDigits(hours) + ':' + this.textUtils.twoDigits(minutes) + ':' + this.textUtils.twoDigits(seconds);
     }
diff --git a/src/providers/app.ts b/src/providers/app.ts
index 7bc1f36be..9679adc9e 100644
--- a/src/providers/app.ts
+++ b/src/providers/app.ts
@@ -40,11 +40,11 @@ export interface CoreRedirectData {
  */
 @Injectable()
 export class CoreAppProvider {
-    DBNAME = 'MoodleMobile';
-    db: SQLiteDB;
-    logger;
-    ssoAuthenticationPromise : Promise<any>;
-    isKeyboardShown: boolean = false;
+    protected DBNAME = 'MoodleMobile';
+    protected db: SQLiteDB;
+    protected logger;
+    protected ssoAuthenticationPromise : Promise<any>;
+    protected isKeyboardShown: boolean = false;
 
     constructor(dbProvider: CoreDbProvider, private platform: Platform, private keyboard: Keyboard, private appCtrl: App,
             private network: Network, logger: CoreLoggerProvider) {
diff --git a/src/providers/config.ts b/src/providers/config.ts
index 88cf788c9..7b9f4970e 100644
--- a/src/providers/config.ts
+++ b/src/providers/config.ts
@@ -22,9 +22,9 @@ import { SQLiteDB } from '../classes/sqlitedb';
  */
 @Injectable()
 export class CoreConfigProvider {
-    appDB: SQLiteDB;
-    TABLE_NAME = 'core_config';
-    tableSchema = {
+    protected appDB: SQLiteDB;
+    protected TABLE_NAME = 'core_config';
+    protected tableSchema = {
         name: this.TABLE_NAME,
         columns: [
             {
diff --git a/src/providers/cron.ts b/src/providers/cron.ts
index c6605700f..b8856769c 100644
--- a/src/providers/cron.ts
+++ b/src/providers/cron.ts
@@ -109,7 +109,7 @@ export class CoreCronDelegate {
 
         if (isSync) {
             // Check network connection.
-            promise = this.configProvider.get(CoreConstants.settingsSyncOnlyOnWifi, false).then((syncOnlyOnWifi) => {
+            promise = this.configProvider.get(CoreConstants.SETTINGS_SYNC_ONLY_ON_WIFI, false).then((syncOnlyOnWifi) => {
                 return !syncOnlyOnWifi || !this.appProvider.isNetworkAccessLimited();
             });
         } else {
diff --git a/src/providers/db.ts b/src/providers/db.ts
index 0a463143e..a3c1f4aab 100644
--- a/src/providers/db.ts
+++ b/src/providers/db.ts
@@ -24,7 +24,7 @@ import { SQLiteDBMock } from '../core/emulator/classes/sqlitedb';
 @Injectable()
 export class CoreDbProvider {
 
-    dbInstances = {};
+    protected dbInstances = {};
 
     constructor(private sqlite: SQLite, private platform: Platform) {}
 
diff --git a/src/providers/events.ts b/src/providers/events.ts
index c586e5925..a9407f618 100644
--- a/src/providers/events.ts
+++ b/src/providers/events.ts
@@ -49,9 +49,9 @@ export class CoreEventsProvider {
     public static APP_LAUNCHED_URL = 'app_launched_url'; // App opened with a certain URL (custom URL scheme).
     public static FILE_SHARED = 'file_shared';
 
-    logger;
-    observables: {[s: string] : Subject<any>} = {};
-    uniqueEvents = {};
+    protected logger;
+    protected observables: {[s: string] : Subject<any>} = {};
+    protected uniqueEvents = {};
 
     constructor(logger: CoreLoggerProvider) {
         this.logger = logger.getInstance('CoreEventsProvider');
diff --git a/src/providers/file.ts b/src/providers/file.ts
index e8c693f8a..53d8d0d0a 100644
--- a/src/providers/file.ts
+++ b/src/providers/file.ts
@@ -27,20 +27,20 @@ import { Zip } from '@ionic-native/zip';
  */
 @Injectable()
 export class CoreFileProvider {
-    logger;
-    initialized = false;
-    basePath = '';
-    isHTMLAPI = false;
+    protected logger;
+    protected initialized = false;
+    protected basePath = '';
+    protected isHTMLAPI = false;
 
     // Formats to read a file.
-    FORMATTEXT         = 0;
-    FORMATDATAURL      = 1;
-    FORMATBINARYSTRING = 2;
-    FORMATARRAYBUFFER  = 3;
+    public static FORMATTEXT         = 0;
+    public static FORMATDATAURL      = 1;
+    public static FORMATBINARYSTRING = 2;
+    public static FORMATARRAYBUFFER  = 3;
 
     // Folders.
-    SITESFOLDER = 'sites';
-    TMPFOLDER = 'tmp';
+    public static SITESFOLDER = 'sites';
+    public static TMPFOLDER = 'tmp';
 
     constructor(logger: CoreLoggerProvider, private platform: Platform, private file: File, private appProvider: CoreAppProvider,
             private textUtils: CoreTextUtilsProvider, private zip: Zip, private mimeUtils: CoreMimetypeUtilsProvider) {
@@ -136,7 +136,7 @@ export class CoreFileProvider {
      * @return {string} Site folder path.
      */
     getSiteFolder(siteId: string) : string {
-        return this.SITESFOLDER + '/' + siteId;
+        return CoreFileProvider.SITESFOLDER + '/' + siteId;
     }
 
     /**
@@ -380,17 +380,17 @@ export class CoreFileProvider {
      *                                  FORMATARRAYBUFFER
      * @return {Promise<any>} Promise to be resolved when the file is read.
      */
-    readFile(path: string, format = this.FORMATTEXT) : Promise<any> {
+    readFile(path: string, format = CoreFileProvider.FORMATTEXT) : Promise<any> {
         // Remove basePath if it's in the path.
         path = this.removeStartingSlash(path.replace(this.basePath, ''));
         this.logger.debug('Read file ' + path + ' with format ' + format);
 
         switch (format) {
-            case this.FORMATDATAURL:
+            case CoreFileProvider.FORMATDATAURL:
                 return this.file.readAsDataURL(this.basePath, path);
-            case this.FORMATBINARYSTRING:
+            case CoreFileProvider.FORMATBINARYSTRING:
                 return this.file.readAsBinaryString(this.basePath, path);
-            case this.FORMATARRAYBUFFER:
+            case CoreFileProvider.FORMATARRAYBUFFER:
                 return this.file.readAsArrayBuffer(this.basePath, path);
             default:
                 return this.file.readAsText(this.basePath, path);
@@ -408,8 +408,8 @@ export class CoreFileProvider {
      *                                  FORMATARRAYBUFFER
      * @return {Promise<any>} Promise to be resolved when the file is read.
      */
-    readFileData(fileData: any, format = this.FORMATTEXT) : Promise<any> {
-        format = format || this.FORMATTEXT;
+    readFileData(fileData: any, format = CoreFileProvider.FORMATTEXT) : Promise<any> {
+        format = format || CoreFileProvider.FORMATTEXT;
         this.logger.debug('Read file from file data with format ' + format);
 
         return new Promise((resolve, reject) => {
@@ -426,13 +426,13 @@ export class CoreFileProvider {
             }
 
             switch (format) {
-                case this.FORMATDATAURL:
+                case CoreFileProvider.FORMATDATAURL:
                     reader.readAsDataURL(fileData);
                     break;
-                case this.FORMATBINARYSTRING:
+                case CoreFileProvider.FORMATBINARYSTRING:
                     reader.readAsBinaryString(fileData);
                     break;
-                case this.FORMATARRAYBUFFER:
+                case CoreFileProvider.FORMATARRAYBUFFER:
                     reader.readAsArrayBuffer(fileData);
                     break;
                 default:
@@ -883,7 +883,7 @@ export class CoreFileProvider {
      * @return {Promise<any>} Promise resolved when done.
      */
     clearTmpFolder() : Promise<any> {
-        return this.removeDir(this.TMPFOLDER);
+        return this.removeDir(CoreFileProvider.TMPFOLDER);
     }
 
     /**
diff --git a/src/providers/filepool.ts b/src/providers/filepool.ts
index a576880ee..879f2e961 100644
--- a/src/providers/filepool.ts
+++ b/src/providers/filepool.ts
@@ -648,7 +648,7 @@ export class CoreFilepoolProvider {
                 return site.getDb().deleteRecords(this.PACKAGES_TABLE).then(() => {
                     entries.forEach((entry) => {
                         // Trigger module status changed, setting it as not downloaded.
-                        this.triggerPackageStatusChanged(siteId, CoreConstants.notDownloaded, entry.component, entry.componentId);
+                        this.triggerPackageStatusChanged(siteId, CoreConstants.NOT_DOWNLOADED, entry.component, entry.componentId);
                     });
                 });
             });
@@ -693,13 +693,13 @@ export class CoreFilepoolProvider {
     /**
      * Given the current status of a list of packages and the status of one of the packages,
      * determine the new status for the list of packages. The status of a list of packages is:
-     *     - CoreConstants.nowDownloadable if there are no downloadable packages.
-     *     - CoreConstants.notDownloaded if at least 1 package has status CoreConstants.notDownloaded.
-     *     - CoreConstants.downloaded if ALL the downloadable packages have status CoreConstants.downloaded.
-     *     - CoreConstants.downloading if ALL the downloadable packages have status CoreConstants.downloading or
-     *                                     CoreConstants.downloaded, with at least 1 package with CoreConstants.downloading.
-     *     - CoreConstants.outdated if ALL the downloadable packages have status CoreConstants.outdated or CoreConstants.downloaded
-     *                                     or CoreConstants.downloading, with at least 1 package with CoreConstants.outdated.
+     *     - CoreConstants.NOT_DOWNLOADABLE if there are no downloadable packages.
+     *     - CoreConstants.NOT_DOWNLOADED if at least 1 package has status CoreConstants.NOT_DOWNLOADED.
+     *     - CoreConstants.DOWNLOADED if ALL the downloadable packages have status CoreConstants.DOWNLOADED.
+     *     - CoreConstants.DOWNLOADING if ALL the downloadable packages have status CoreConstants.DOWNLOADING or
+     *                                     CoreConstants.DOWNLOADED, with at least 1 package with CoreConstants.DOWNLOADING.
+     *     - CoreConstants.OUTDATED if ALL the downloadable packages have status CoreConstants.OUTDATED or CoreConstants.DOWNLOADED
+     *                                     or CoreConstants.DOWNLOADING, with at least 1 package with CoreConstants.OUTDATED.
      *
      * @param {string} current Current status of the list of packages.
      * @param {string} packagestatus Status of one of the packages.
@@ -707,22 +707,22 @@ export class CoreFilepoolProvider {
      */
     determinePackagesStatus(current: string, packageStatus: string) : string {
         if (!current) {
-            current = CoreConstants.notDownloadable;
+            current = CoreConstants.NOT_DOWNLOADABLE;
         }
 
-        if (packageStatus === CoreConstants.notDownloaded) {
+        if (packageStatus === CoreConstants.NOT_DOWNLOADED) {
             // If 1 package is not downloaded the status of the whole list will always be not downloaded.
-            return CoreConstants.notDownloaded;
-        } else if (packageStatus === CoreConstants.downloaded && current === CoreConstants.notDownloadable) {
+            return CoreConstants.NOT_DOWNLOADED;
+        } else if (packageStatus === CoreConstants.DOWNLOADED && current === CoreConstants.NOT_DOWNLOADABLE) {
             // If all packages are downloaded or not downloadable with at least 1 downloaded, status will be downloaded.
-            return CoreConstants.downloaded;
-        } else if (packageStatus === CoreConstants.downloading &&
-                (current === CoreConstants.notDownloadable || current === CoreConstants.downloaded)) {
+            return CoreConstants.DOWNLOADED;
+        } else if (packageStatus === CoreConstants.DOWNLOADING &&
+                (current === CoreConstants.NOT_DOWNLOADABLE || current === CoreConstants.DOWNLOADED)) {
             // If all packages are downloading/downloaded/notdownloadable with at least 1 downloading, status will be downloading.
-            return CoreConstants.downloading;
-        } else if (packageStatus === CoreConstants.outdated && current !== CoreConstants.notDownloaded) {
+            return CoreConstants.DOWNLOADING;
+        } else if (packageStatus === CoreConstants.OUTDATED && current !== CoreConstants.NOT_DOWNLOADED) {
             // If there are no packages notdownloaded and there is at least 1 outdated, status will be outdated.
-            return CoreConstants.outdated;
+            return CoreConstants.OUTDATED;
         }
 
         // Status remains the same.
@@ -865,7 +865,7 @@ export class CoreFilepoolProvider {
         timemodified = timemodified || this.getTimemodifiedFromFileList(fileList);
 
         // Set package as downloading.
-        promise = this.storePackageStatus(siteId, CoreConstants.downloading, component, componentId).then(() => {
+        promise = this.storePackageStatus(siteId, CoreConstants.DOWNLOADING, component, componentId).then(() => {
             let promises = [],
                 packageLoaded = 0;
 
@@ -919,7 +919,7 @@ export class CoreFilepoolProvider {
 
             return Promise.all(promises).then(() => {
                 // Success prefetching, store package as downloaded.
-                return this.storePackageStatus(siteId, CoreConstants.downloaded, component, componentId, revision, timemodified);
+                return this.storePackageStatus(siteId, CoreConstants.DOWNLOADED, component, componentId, revision, timemodified);
             }).catch(() => {
                 // Error downloading, go back to previous status and reject the promise.
                 return this.setPackagePreviousStatus(siteId, component, componentId).then(() => {
@@ -1391,7 +1391,7 @@ export class CoreFilepoolProvider {
 
             // Check if the file is in queue (waiting to be downloaded).
             return this.hasFileInQueue(siteId, fileId).then(() => {
-                return CoreConstants.downloading;
+                return CoreConstants.DOWNLOADING;
             }).catch(() => {
                 // Check if the file is being downloaded right now.
                 let extension = this.mimeUtils.guessExtensionFromUrl(fileUrl),
@@ -1400,18 +1400,18 @@ export class CoreFilepoolProvider {
                 return Promise.resolve(path).then((filePath) => {
                     const downloadId = this.getFileDownloadId(fileUrl, filePath);
                     if (this.filePromises[siteId] && this.filePromises[siteId][downloadId]) {
-                        return CoreConstants.downloading;
+                        return CoreConstants.DOWNLOADING;
                     }
 
                     // File is not being downloaded. Check if it's downloaded and if it's outdated.
                     return this.hasFileInPool(siteId, fileId).then((entry) => {
                         if (this.isFileOutdated(entry, revision, timemodified)) {
-                            return CoreConstants.outdated;
+                            return CoreConstants.OUTDATED;
                         } else {
-                            return CoreConstants.downloaded;
+                            return CoreConstants.DOWNLOADED;
                         }
                     }).catch(() => {
-                        return CoreConstants.notDownloaded;
+                        return CoreConstants.NOT_DOWNLOADED;
                     });
                 });
             });
@@ -1584,9 +1584,9 @@ export class CoreFilepoolProvider {
      */
     getPackageCurrentStatus(siteId: string, component: string, componentId?: string|number) : Promise<string> {
         return this.getPackageData(siteId, component, componentId).then((entry) => {
-            return entry.status || CoreConstants.notDownloaded;
+            return entry.status || CoreConstants.NOT_DOWNLOADED;
         }).catch(() => {
-            return CoreConstants.notDownloaded;
+            return CoreConstants.NOT_DOWNLOADED;
         });
     }
 
@@ -1705,9 +1705,9 @@ export class CoreFilepoolProvider {
      */
     getPackagePreviousStatus(siteId: string, component: string, componentId?: string|number) : Promise<string> {
         return this.getPackageData(siteId, component, componentId).then((entry) => {
-            return entry.previous || CoreConstants.notDownloaded;
+            return entry.previous || CoreConstants.NOT_DOWNLOADED;
         }).catch(() => {
-            return CoreConstants.notDownloaded;
+            return CoreConstants.NOT_DOWNLOADED;
         });
     }
 
@@ -1745,34 +1745,34 @@ export class CoreFilepoolProvider {
 
             // Get status.
             return site.getDb().getRecord(this.PACKAGES_TABLE, conditions).then((entry: CoreFilepoolPackageEntry) => {
-                if (entry.status === CoreConstants.downloaded) {
+                if (entry.status === CoreConstants.DOWNLOADED) {
                     if (revision != entry.revision || timemodified > entry.timemodified) {
                         // File is outdated. Let's change its status.
                         let newData: CoreFilepoolPackageEntry = {
-                            status: CoreConstants.outdated,
+                            status: CoreConstants.OUTDATED,
                             updated: Date.now()
                         };
                         site.getDb().updateRecords(this.PACKAGES_TABLE, newData, conditions).then(() => {
                             // Success inserting, trigger event.
-                            this.triggerPackageStatusChanged(siteId, CoreConstants.outdated, component, componentId);
+                            this.triggerPackageStatusChanged(siteId, CoreConstants.OUTDATED, component, componentId);
                         });
                     }
-                } else if (entry.status === CoreConstants.outdated) {
+                } else if (entry.status === CoreConstants.OUTDATED) {
                     if (revision === entry.revision && timemodified === entry.timemodified) {
                         // File isn't outdated anymore. Let's change its status.
                         let newData: CoreFilepoolPackageEntry = {
-                            status: CoreConstants.downloaded,
+                            status: CoreConstants.DOWNLOADED,
                             updated: Date.now()
                         };
                         site.getDb().updateRecords(this.PACKAGES_TABLE, newData, conditions).then(() => {
                             // Success inserting, trigger event.
-                            this.triggerPackageStatusChanged(siteId, CoreConstants.downloaded, component, componentId);
+                            this.triggerPackageStatusChanged(siteId, CoreConstants.DOWNLOADED, component, componentId);
                         });
                     }
                 }
                 return entry.status;
             }, () => {
-                return CoreConstants.notDownloaded;
+                return CoreConstants.NOT_DOWNLOADED;
             });
         });
     }
@@ -2511,11 +2511,11 @@ export class CoreFilepoolProvider {
             // Get current stored data, we'll only update 'status' and 'updated' fields.
             return site.getDb().getRecord(this.PACKAGES_TABLE, {id: packageId}).then((entry: CoreFilepoolPackageEntry) => {
                 let newData: CoreFilepoolPackageEntry = {};
-                if (entry.status == CoreConstants.downloading) {
+                if (entry.status == CoreConstants.DOWNLOADING) {
                     // Going back from downloading to previous status, restore previous download time.
                     newData.downloadTime = entry.previousDownloadTime;
                 }
-                newData.status = entry.previous || CoreConstants.downloaded;
+                newData.status = entry.previous || CoreConstants.DOWNLOADED;
                 newData.updated = Date.now();
                 this.logger.debug(`Set previous status '${entry.status}' for package ${component} ${componentId}`);
 
@@ -2582,7 +2582,7 @@ export class CoreFilepoolProvider {
                 downloadTime,
                 previousDownloadTime;
 
-            if (status == CoreConstants.downloading) {
+            if (status == CoreConstants.DOWNLOADING) {
                 // Set download time if package is now downloading.
                 downloadTime = this.timeUtils.timestamp();
             }
diff --git a/src/providers/groups.ts b/src/providers/groups.ts
index 0762719dc..43411b139 100644
--- a/src/providers/groups.ts
+++ b/src/providers/groups.ts
@@ -31,6 +31,7 @@ export class CoreGroupsProvider {
     public static NOGROUPS       = 0;
     public static SEPARATEGROUPS = 1;
     public static VISIBLEGROUPS  = 2;
+    protected ROOT_CACHE_KEY = 'mmGroups:';
 
     constructor(private sitesProvider: CoreSitesProvider, private translate: TranslateService) {}
 
@@ -86,7 +87,7 @@ export class CoreGroupsProvider {
      * @return {string} Cache key.
      */
     protected getActivityAllowedGroupsCacheKey(cmId: number, userId: number) : string {
-        return this.getRootCacheKey() + 'allowedgroups:' + cmId + ':' + userId;
+        return this.ROOT_CACHE_KEY + 'allowedgroups:' + cmId + ':' + userId;
     }
 
     /**
@@ -178,16 +179,7 @@ export class CoreGroupsProvider {
      * @return {string} Cache key.
      */
     protected getActivityGroupModeCacheKey(cmId: number) : string {
-        return this.getRootCacheKey() + 'groupmode:' + cmId;
-    }
-
-    /**
-     * Get the "root" cache key for WS calls.
-     *
-     * @return {string} Cache key.
-     */
-    protected getRootCacheKey() : string {
-        return 'mmGroups:';
+        return this.ROOT_CACHE_KEY + 'groupmode:' + cmId;
     }
 
     /**
@@ -249,7 +241,7 @@ export class CoreGroupsProvider {
      * @return {string} Cache key.
      */
     protected getUserGroupsInCourseCacheKey(courseId: number, userId: number) : string {
-        return this.getRootCacheKey() + 'courseGroups:' + courseId + ':' + userId;
+        return this.ROOT_CACHE_KEY + 'courseGroups:' + courseId + ':' + userId;
     }
 
     /**
diff --git a/src/providers/init.ts b/src/providers/init.ts
index 37dd18ab2..dc08fc64b 100644
--- a/src/providers/init.ts
+++ b/src/providers/init.ts
@@ -32,9 +32,9 @@ export class CoreInitDelegate {
     public static DEFAULT_PRIORITY = 100; // Default priority for init processes.
     public static MAX_RECOMMENDED_PRIORITY = 600;
 
-    initProcesses = {};
-    logger;
-    readiness;
+    protected initProcesses = {};
+    protected logger;
+    protected readiness;
 
     constructor(logger: CoreLoggerProvider, platform: Platform, private utils: CoreUtilsProvider) {
         this.logger = logger.getInstance('CoreInitDelegate');
diff --git a/src/providers/lang.ts b/src/providers/lang.ts
index 86b241c9a..af62d6268 100644
--- a/src/providers/lang.ts
+++ b/src/providers/lang.ts
@@ -26,10 +26,10 @@ import { CoreConfigConstants } from '../configconstants';
 */
 @Injectable()
 export class CoreLangProvider {
-    fallbackLanguage:string = 'en'; // mmCoreConfigConstants.default_lang || 'en',
-    currentLanguage: string; // Save current language in a variable to speed up the get function.
-    customStrings = {};
-    customStringsRaw: string;
+    protected fallbackLanguage:string = 'en'; // mmCoreConfigConstants.default_lang || 'en',
+    protected currentLanguage: string; // Save current language in a variable to speed up the get function.
+    protected customStrings = {};
+    protected customStringsRaw: string;
 
     constructor(private translate: TranslateService, private configProvider: CoreConfigProvider, platform: Platform,
             private globalization: Globalization) {
diff --git a/src/providers/local-notifications.ts b/src/providers/local-notifications.ts
index c95ef78c4..2a7f6e68c 100644
--- a/src/providers/local-notifications.ts
+++ b/src/providers/local-notifications.ts
@@ -432,7 +432,7 @@ export class CoreLocalNotificationsProvider {
         return this.isTriggered(notification).then((triggered) => {
             if (!triggered) {
                 // Check if sound is enabled for notifications.
-                return this.configProvider.get(CoreConstants.settingsNotificationSound, true).then((soundEnabled) => {
+                return this.configProvider.get(CoreConstants.SETTINGS_NOTIFICATION_SOUND, true).then((soundEnabled) => {
                     if (!soundEnabled) {
                         notification.sound = null;
                     } else {
diff --git a/src/providers/sites.ts b/src/providers/sites.ts
index e912ef2bf..45c6bceca 100644
--- a/src/providers/sites.ts
+++ b/src/providers/sites.ts
@@ -234,7 +234,7 @@ export class CoreSitesProvider {
                 this.services[siteUrl] = data.service; // No need to store it in DB.
 
                 if (data.coreSupported ||
-                        (data.code != CoreConstants.loginSSOCode && data.code != CoreConstants.loginSSOInAppCode)) {
+                        (data.code != CoreConstants.LOGIN_SSO_CODE && data.code != CoreConstants.LOGIN_SSO_INAPP_CODE)) {
                     // SSO using local_mobile not needed, try to get the site public config.
                     return temporarySite.getPublicConfig().then((config) : any => {
                         publicConfig = config;
@@ -301,7 +301,7 @@ export class CoreSitesProvider {
             data.service = 'c';
         }
 
-        const observable = this.http.post(siteUrl + '/login/token.php', data).timeout(CoreConstants.wsTimeout);
+        const observable = this.http.post(siteUrl + '/login/token.php', data).timeout(CoreConstants.WS_TIMEOUT);
         return this.utils.observableToPromise(observable).catch((error) => {
             return Promise.reject(error.message);
         }).then((data: any) => {
@@ -339,7 +339,7 @@ export class CoreSitesProvider {
                 password: password,
                 service: service
             },
-            observable = this.http.post(siteUrl + '/login/token.php', params).timeout(CoreConstants.wsTimeout);
+            observable = this.http.post(siteUrl + '/login/token.php', params).timeout(CoreConstants.WS_TIMEOUT);
 
         return this.utils.observableToPromise(observable).then((data: any) : any => {
             if (typeof data == 'undefined') {
diff --git a/src/providers/utils/dom.ts b/src/providers/utils/dom.ts
index 3a3edbbb6..73e377e93 100644
--- a/src/providers/utils/dom.ts
+++ b/src/providers/utils/dom.ts
@@ -27,11 +27,13 @@ import { CoreConstants } from '../../core/constants';
  */
 @Injectable()
 export class CoreDomUtilsProvider {
-    element = document.createElement('div'); // Fake element to use in some functions, to prevent re-creating it each time.
-    matchesFn: string; // Name of the "matches" function to use when simulating a closest call.
-    inputSupportKeyboard = ['date', 'datetime', 'datetime-local', 'email', 'month', 'number', 'password',
+    // List of input types that support keyboard.
+    protected INPUT_SUPPORT_KEYBOARD = ['date', 'datetime', 'datetime-local', 'email', 'month', 'number', 'password',
                 'search', 'tel', 'text', 'time', 'url', 'week'];
 
+    protected element = document.createElement('div'); // Fake element to use in some functions, to prevent creating it each time.
+    protected matchesFn: string; // Name of the "matches" function to use when simulating a closest call.
+
     constructor(private translate: TranslateService, private loadingCtrl: LoadingController, private toastCtrl: ToastController,
         private alertCtrl: AlertController, private textUtils: CoreTextUtilsProvider, private appProvider: CoreAppProvider,
         private platform: Platform, private configProvider: CoreConfigProvider, private urlUtils: CoreUrlUtilsProvider,
@@ -103,8 +105,8 @@ export class CoreDomUtilsProvider {
      */
     confirmDownloadSize(size: any, message?: string, unknownMessage?: string, wifiThreshold?: number, limitedThreshold?: number)
             : Promise<void> {
-        wifiThreshold = typeof wifiThreshold == 'undefined' ? CoreConstants.wifiDownloadThreshold : wifiThreshold;
-        limitedThreshold = typeof limitedThreshold == 'undefined' ? CoreConstants.downloadThreshold : limitedThreshold;
+        wifiThreshold = typeof wifiThreshold == 'undefined' ? CoreConstants.WIFI_DOWNLOAD_THRESHOLD : wifiThreshold;
+        limitedThreshold = typeof limitedThreshold == 'undefined' ? CoreConstants.DOWNLOAD_THRESHOLD : limitedThreshold;
 
         if (size.size < 0 || (size.size == 0 && !size.total)) {
             // Seems size was unable to be calculated. Show a warning.
@@ -424,7 +426,7 @@ export class CoreDomUtilsProvider {
      */
     isRichTextEditorEnabled() : Promise<boolean> {
         if (this.isRichTextEditorSupported()) {
-            return this.configProvider.get(CoreConstants.settingsRichTextEditor, true);
+            return this.configProvider.get(CoreConstants.SETTINGS_RICH_TEXT_EDITOR, true);
         }
 
         return Promise.resolve(false);
@@ -729,7 +731,7 @@ export class CoreDomUtilsProvider {
      * @return {Alert} The alert modal.
      */
     showErrorModalDefault(error: any, defaultError: any, needsTranslate?: boolean, autocloseTime?: number) : Alert {
-        if (error != CoreConstants.dontShowError) {
+        if (error != CoreConstants.DONT_SHOW_ERROR) {
             if (error && typeof error != 'string') {
                 error = error.message || error.error;
             }
@@ -839,7 +841,7 @@ export class CoreDomUtilsProvider {
      */
     supportsInputKeyboard(el: any) : boolean {
         return el && !el.disabled && (el.tagName.toLowerCase() == 'textarea' ||
-            (el.tagName.toLowerCase() == 'input' && this.inputSupportKeyboard.indexOf(el.type) != -1));
+            (el.tagName.toLowerCase() == 'input' && this.INPUT_SUPPORT_KEYBOARD.indexOf(el.type) != -1));
     }
 
     /**
diff --git a/src/providers/utils/mimetype.ts b/src/providers/utils/mimetype.ts
index 096365aaf..fce9e3cd0 100644
--- a/src/providers/utils/mimetype.ts
+++ b/src/providers/utils/mimetype.ts
@@ -23,12 +23,12 @@ import { CoreTextUtilsProvider } from './text';
  */
 @Injectable()
 export class CoreMimetypeUtilsProvider {
-    logger;
-    extToMime = {}; // Object to map extensions -> mimetypes.
-    mimeToExt = {}; // Object to map mimetypes -> extensions.
-    groupsMimeInfo = {}; // Object to hold extensions and mimetypes that belong to a certain "group" (audio, video, ...).
-    extensionRegex = /^[a-z0-9]+$/;
-    wsProvider: any = {}; // @todo
+    protected logger;
+    protected extToMime = {}; // Object to map extensions -> mimetypes.
+    protected mimeToExt = {}; // Object to map mimetypes -> extensions.
+    protected groupsMimeInfo = {}; // Object to hold extensions and mimetypes that belong to a certain "group" (audio, video, ...).
+    protected extensionRegex = /^[a-z0-9]+$/;
+    protected wsProvider: any = {}; // @todo
 
     constructor(http: HttpClient, logger: CoreLoggerProvider, private translate: TranslateService,
             private textUtils: CoreTextUtilsProvider) {
diff --git a/src/providers/utils/text.ts b/src/providers/utils/text.ts
index e045adc01..587f2f1fd 100644
--- a/src/providers/utils/text.ts
+++ b/src/providers/utils/text.ts
@@ -22,7 +22,7 @@ import { CoreLangProvider } from '../lang';
 */
 @Injectable()
 export class CoreTextUtilsProvider {
-    element = document.createElement('div'); // Fake element to use in some functions, to prevent re-creating it each time.
+    protected element = document.createElement('div'); // Fake element to use in some functions, to prevent creating it each time.
 
     constructor(private translate: TranslateService, private langProvider: CoreLangProvider, private modalCtrl: ModalController) {}
 
diff --git a/src/providers/utils/time.ts b/src/providers/utils/time.ts
index f4deaa138..3382e77eb 100644
--- a/src/providers/utils/time.ts
+++ b/src/providers/utils/time.ts
@@ -33,17 +33,17 @@ export class CoreTimeUtilsProvider {
      */
     formatTime(seconds: number) : string {
         let totalSecs = Math.abs(seconds),
-            years     = Math.floor(totalSecs / CoreConstants.secondsYear),
-            remainder = totalSecs - (years * CoreConstants.secondsYear),
-            days      = Math.floor(remainder / CoreConstants.secondsDay);
+            years     = Math.floor(totalSecs / CoreConstants.SECONDS_YEAR),
+            remainder = totalSecs - (years * CoreConstants.SECONDS_YEAR),
+            days      = Math.floor(remainder / CoreConstants.SECONDS_DAY);
 
-        remainder = totalSecs - (days * CoreConstants.secondsDay);
+        remainder = totalSecs - (days * CoreConstants.SECONDS_DAY);
 
-        let hours = Math.floor(remainder / CoreConstants.secondsHour);
-        remainder = remainder - (hours * CoreConstants.secondsHour);
+        let hours = Math.floor(remainder / CoreConstants.SECONDS_HOUR);
+        remainder = remainder - (hours * CoreConstants.SECONDS_HOUR);
 
-        let mins = Math.floor(remainder / CoreConstants.secondsMinute),
-            secs      = remainder - (mins * CoreConstants.secondsMinute),
+        let mins = Math.floor(remainder / CoreConstants.SECONDS_MINUTE),
+            secs      = remainder - (mins * CoreConstants.SECONDS_MINUTE),
             ss = this.translate.instant('core.' + (secs == 1 ? 'sec' : 'secs')),
             sm = this.translate.instant('core.' + (mins == 1 ? 'min' : 'mins')),
             sh = this.translate.instant('core.' + (hours == 1 ? 'hour' : 'hours')),
diff --git a/src/providers/utils/utils.ts b/src/providers/utils/utils.ts
index c2a084f09..fec2cc4b7 100644
--- a/src/providers/utils/utils.ts
+++ b/src/providers/utils/utils.ts
@@ -35,8 +35,8 @@ export interface PromiseDefer {
  */
 @Injectable()
 export class CoreUtilsProvider {
-    logger;
-    iabInstance: InAppBrowserObject;
+    protected logger;
+    protected iabInstance: InAppBrowserObject;
 
     constructor(private iab: InAppBrowser, private appProvider: CoreAppProvider, private clipboard: Clipboard,
             private domUtils: CoreDomUtilsProvider, logger: CoreLoggerProvider, private translate: TranslateService,
diff --git a/src/providers/ws.ts b/src/providers/ws.ts
index 02d04fba4..e6002cd3b 100644
--- a/src/providers/ws.ts
+++ b/src/providers/ws.ts
@@ -68,11 +68,11 @@ export interface CoreWSFileUploadOptions extends FileUploadOptions {
  */
 @Injectable()
 export class CoreWSProvider {
-    logger;
-    mimeTypeCache = {}; // A "cache" to store file mimetypes to prevent performing too many HEAD requests.
-    ongoingCalls = {};
-    retryCalls = [];
-    retryTimeout = 0;
+    protected logger;
+    protected mimeTypeCache = {}; // A "cache" to store file mimetypes to prevent performing too many HEAD requests.
+    protected ongoingCalls = {};
+    protected retryCalls = [];
+    protected retryTimeout = 0;
 
     constructor(private http: HttpClient, private translate: TranslateService, private appProvider: CoreAppProvider,
             private textUtils: CoreTextUtilsProvider, logger: CoreLoggerProvider, private utils: CoreUtilsProvider,
@@ -180,7 +180,7 @@ export class CoreWSProvider {
 
         siteUrl = preSets.siteUrl + '/lib/ajax/service.php';
 
-        let observable = this.http.post(siteUrl, JSON.stringify(ajaxData)).timeout(CoreConstants.wsTimeout);
+        let observable = this.http.post(siteUrl, JSON.stringify(ajaxData)).timeout(CoreConstants.WS_TIMEOUT);
         return this.utils.observableToPromise(observable).then((data: any) => {
             // Some moodle web services return null. If the responseExpected value is set then so long as no data
             // is returned, we create a blank object.
@@ -436,7 +436,7 @@ export class CoreWSProvider {
         let promise = this.getPromiseHttp('head', url);
 
         if (!promise) {
-            promise = this.utils.observableToPromise(this.commonHttp.head(url).timeout(CoreConstants.wsTimeout));
+            promise = this.utils.observableToPromise(this.commonHttp.head(url).timeout(CoreConstants.WS_TIMEOUT));
             promise = this.setPromiseHttp(promise, 'head', url);
         }
 
@@ -454,7 +454,7 @@ export class CoreWSProvider {
      */
     performPost(method: string, siteUrl: string, ajaxData: any, preSets: CoreWSPreSets) : Promise<any> {
         // Perform the post request.
-        let observable = this.http.post(siteUrl, ajaxData).timeout(CoreConstants.wsTimeout),
+        let observable = this.http.post(siteUrl, ajaxData).timeout(CoreConstants.WS_TIMEOUT),
             promise;
 
         promise = this.utils.observableToPromise(observable).then((data: any) => {
@@ -547,7 +547,7 @@ export class CoreWSProvider {
         // HTTP not finished, but we should delete the promise after timeout.
         timeout = setTimeout(() => {
             delete this.ongoingCalls[queueItemId];
-        }, CoreConstants.wsTimeout);
+        }, CoreConstants.WS_TIMEOUT);
 
         // HTTP finished, delete from ongoing.
         return promise.finally(() => {