diff --git a/src/addon/mod/choice/components/index/addon-mod-choice-index.html b/src/addon/mod/choice/components/index/addon-mod-choice-index.html
index a9e81b5f6..cfeaddc5f 100644
--- a/src/addon/mod/choice/components/index/addon-mod-choice-index.html
+++ b/src/addon/mod/choice/components/index/addon-mod-choice-index.html
@@ -19,13 +19,13 @@
     <!-- Activity availability messages -->
     <ion-card class="core-info-card" icon-start *ngIf="choiceNotOpenYet">
         <ion-icon name="information-circle"></ion-icon>
-        <p *ngIf="options && options.length">{{ 'addon.mod_choice.previewonly' | translate:{$a: choice.openTimeReadable} }}</p>
-        <p *ngIf="!options || !options.length">{{ 'addon.mod_choice.notopenyet' | translate:{$a: choice.openTimeReadable} }}</p>
+        <p *ngIf="options && options.length">{{ 'addon.mod_choice.previewonly' | translate:{$a: openTimeReadable} }}</p>
+        <p *ngIf="!options || !options.length">{{ 'addon.mod_choice.notopenyet' | translate:{$a: openTimeReadable} }}</p>
     </ion-card>
     <ion-card class="core-info-card" icon-start *ngIf="choiceClosed">
         <ion-icon name="information-circle"></ion-icon>
         <p *ngIf="options && options.length">{{ 'addon.mod_choice.yourselection' | translate }} <core-format-text [text]="options[0].text"></core-format-text></p>
-        <p>{{ 'addon.mod_choice.expired' | translate:{$a: choice.closeTimeReadable} }}</p>
+        <p>{{ 'addon.mod_choice.expired' | translate:{$a: closeTimeReadable} }}</p>
     </ion-card>
 
     <!-- Choice done in offline but not synchronized -->
@@ -80,7 +80,7 @@
                     <ion-item-group *ngFor="let result of results">
                         <ion-item-divider text-wrap>
                             <h2><core-format-text [text]="result.text"></core-format-text></h2>
-                            <p>{{ 'addon.mod_choice.numberofuser' | translate }}: {{ result.numberofuser }} ({{ 'core.percentagenumber' | translate: {$a: result.percentageamount} }})</p>
+                            <p>{{ 'addon.mod_choice.numberofuser' | translate }}: {{ result.numberofuser }} ({{ 'core.percentagenumber' | translate: {$a: result.percentageamountfixed} }})</p>
                         </ion-item-divider>
                         <a ion-item *ngFor="let user of result.userresponses" core-user-link [courseId]="courseid" [userId]="user.userid" [title]="user.fullname" text-wrap>
                             <ion-avatar core-user-avatar [user]="user" item-start [courseId]="courseid"></ion-avatar>
diff --git a/src/addon/mod/choice/components/index/index.ts b/src/addon/mod/choice/components/index/index.ts
index c5bcdc852..6e3b5799e 100644
--- a/src/addon/mod/choice/components/index/index.ts
+++ b/src/addon/mod/choice/components/index/index.ts
@@ -16,7 +16,7 @@ import { Component, Optional, Injector } from '@angular/core';
 import { Content } from 'ionic-angular';
 import { CoreTimeUtilsProvider } from '@providers/utils/time';
 import { CoreCourseModuleMainActivityComponent } from '@core/course/classes/main-activity-component';
-import { AddonModChoiceProvider } from '../../providers/choice';
+import { AddonModChoiceProvider, AddonModChoiceChoice, AddonModChoiceOption, AddonModChoiceResult } from '../../providers/choice';
 import { AddonModChoiceOfflineProvider } from '../../providers/offline';
 import { AddonModChoiceSyncProvider } from '../../providers/sync';
 
@@ -31,9 +31,9 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
     component = AddonModChoiceProvider.COMPONENT;
     moduleName = 'choice';
 
-    choice: any;
-    options = [];
-    selectedOption: any;
+    choice: AddonModChoiceChoice;
+    options: AddonModChoiceOption[] = [];
+    selectedOption: {id: number};
     choiceNotOpenYet = false;
     choiceClosed = false;
     canEdit = false;
@@ -43,6 +43,8 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
     labels = [];
     results = [];
     publishInfo: string; // Message explaining the user what will happen with his choices.
+    openTimeReadable: string;
+    closeTimeReadable: string;
 
     protected userId: number;
     protected syncEventName = AddonModChoiceSyncProvider.AUTO_SYNCED;
@@ -122,12 +124,12 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
 
         return this.choiceProvider.getChoice(this.courseId, this.module.id).then((choice) => {
             this.choice = choice;
-            this.choice.timeopen = parseInt(choice.timeopen) * 1000;
-            this.choice.openTimeReadable = this.timeUtils.userDate(choice.timeopen);
-            this.choice.timeclose = parseInt(choice.timeclose) * 1000;
-            this.choice.closeTimeReadable = this.timeUtils.userDate(choice.timeclose);
+            this.choice.timeopen = choice.timeopen * 1000;
+            this.choice.timeclose = choice.timeclose * 1000;
+            this.openTimeReadable = this.timeUtils.userDate(choice.timeopen);
+            this.closeTimeReadable = this.timeUtils.userDate(choice.timeclose);
 
-            this.description = choice.intro || choice.description;
+            this.description = choice.intro;
             this.choiceNotOpenYet = choice.timeopen && choice.timeopen > this.now;
             this.choiceClosed = choice.timeclose && choice.timeclose <= this.now;
 
@@ -175,7 +177,7 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
 
             if (hasOffline) {
                 promise = this.choiceOffline.getResponse(this.choice.id).then((response) => {
-                    const optionsKeys = {};
+                    const optionsKeys: {[id: number]: AddonModChoiceOption} = {};
                     options.forEach((option) => {
                         optionsKeys[option.id] = option;
                     });
@@ -223,7 +225,7 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
                 promise = Promise.resolve(options);
             }
 
-            promise.then((options) => {
+            promise.then((options: AddonModChoiceOption[]) => {
                 const isOpen = this.isChoiceOpen();
 
                 let hasAnswered = false;
@@ -291,11 +293,11 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
             let hasVotes = false;
             this.data = [];
             this.labels = [];
-            results.forEach((result) => {
+            results.forEach((result: AddonModChoiceResultFormatted) => {
                 if (result.numberofuser > 0) {
                     hasVotes = true;
                 }
-                result.percentageamount = parseFloat(result.percentageamount).toFixed(1);
+                result.percentageamountfixed = result.percentageamount.toFixed(1);
                 this.data.push(result.numberofuser);
                 this.labels.push(result.text);
             });
@@ -429,3 +431,10 @@ export class AddonModChoiceIndexComponent extends CoreCourseModuleMainActivityCo
         return result.updated;
     }
 }
+
+/**
+ * Choice result with some calculated data.
+ */
+export type AddonModChoiceResultFormatted = AddonModChoiceResult & {
+    percentageamountfixed: string; // Percentage of users answers with fixed decimals.
+};
diff --git a/src/addon/mod/choice/providers/choice.ts b/src/addon/mod/choice/providers/choice.ts
index b16119516..246903592 100644
--- a/src/addon/mod/choice/providers/choice.ts
+++ b/src/addon/mod/choice/providers/choice.ts
@@ -20,6 +20,7 @@ import { CoreFilepoolProvider } from '@providers/filepool';
 import { CoreCourseLogHelperProvider } from '@core/course/providers/log-helper';
 import { AddonModChoiceOfflineProvider } from './offline';
 import { CoreSite, CoreSiteWSPreSets } from '@classes/site';
+import { CoreWSExternalWarning, CoreWSExternalFile } from '@providers/ws';
 
 /**
  * Service that provides some features for choices.
@@ -118,7 +119,9 @@ export class AddonModChoiceProvider {
                 responses: responses
             };
 
-            return site.write('mod_choice_delete_choice_responses', params).then((response) => {
+            return site.write('mod_choice_delete_choice_responses', params)
+                    .then((response: AddonModChoiceDeleteChoiceResponsesResult) => {
+
                 // Other errors ocurring.
                 if (!response || response.status === false) {
                     return Promise.reject(this.utils.createFakeWSError(''));
@@ -179,7 +182,7 @@ export class AddonModChoiceProvider {
      * @return Promise resolved when the choice is retrieved.
      */
     protected getChoiceByDataKey(siteId: string, courseId: number, key: string, value: any, forceCache?: boolean,
-            ignoreCache?: boolean): Promise<any> {
+            ignoreCache?: boolean): Promise<AddonModChoiceChoice> {
 
         return this.sitesProvider.getSite(siteId).then((site) => {
             const params = {
@@ -198,7 +201,9 @@ export class AddonModChoiceProvider {
                 preSets.emergencyCache = false;
             }
 
-            return site.read('mod_choice_get_choices_by_courses', params, preSets).then((response) => {
+            return site.read('mod_choice_get_choices_by_courses', params, preSets)
+                    .then((response: AddonModChoiceGetChoicesByCoursesResult): any => {
+
                 if (response && response.choices) {
                     const currentChoice = response.choices.find((choice) => choice[key] == value);
                     if (currentChoice) {
@@ -221,7 +226,8 @@ export class AddonModChoiceProvider {
      * @param ignoreCache True if it should ignore cached data (it will always fail in offline or server down).
      * @return Promise resolved when the choice is retrieved.
      */
-    getChoice(courseId: number, cmId: number, siteId?: string, forceCache?: boolean, ignoreCache?: boolean): Promise<any> {
+    getChoice(courseId: number, cmId: number, siteId?: string, forceCache?: boolean, ignoreCache?: boolean)
+            : Promise<AddonModChoiceChoice> {
         return this.getChoiceByDataKey(siteId, courseId, 'coursemodule', cmId, forceCache, ignoreCache);
     }
 
@@ -235,7 +241,8 @@ export class AddonModChoiceProvider {
      * @param ignoreCache True if it should ignore cached data (it will always fail in offline or server down).
      * @return Promise resolved when the choice is retrieved.
      */
-    getChoiceById(courseId: number, choiceId: number, siteId?: string, forceCache?: boolean, ignoreCache?: boolean): Promise<any> {
+    getChoiceById(courseId: number, choiceId: number, siteId?: string, forceCache?: boolean, ignoreCache?: boolean)
+            : Promise<AddonModChoiceChoice> {
         return this.getChoiceByDataKey(siteId, courseId, 'id', choiceId, forceCache, ignoreCache);
     }
 
@@ -247,7 +254,7 @@ export class AddonModChoiceProvider {
      * @param siteId Site ID. If not defined, current site.
      * @return Promise resolved with choice options.
      */
-    getOptions(choiceId: number, ignoreCache?: boolean, siteId?: string): Promise<any> {
+    getOptions(choiceId: number, ignoreCache?: boolean, siteId?: string): Promise<AddonModChoiceOption[]> {
         return this.sitesProvider.getSite(siteId).then((site) => {
             const params = {
                 choiceid: choiceId
@@ -262,7 +269,9 @@ export class AddonModChoiceProvider {
                 preSets.emergencyCache = false;
             }
 
-            return site.read('mod_choice_get_choice_options', params, preSets).then((response) => {
+            return site.read('mod_choice_get_choice_options', params, preSets)
+                    .then((response: AddonModChoiceGetChoiceOptionsResult): any => {
+
                 if (response.options) {
                     return response.options;
                 }
@@ -280,7 +289,7 @@ export class AddonModChoiceProvider {
      * @param siteId Site ID. If not defined, current site.
      * @return Promise resolved with choice results.
      */
-    getResults(choiceId: number, ignoreCache?: boolean, siteId?: string): Promise<any> {
+    getResults(choiceId: number, ignoreCache?: boolean, siteId?: string): Promise<AddonModChoiceResult[]> {
         return this.sitesProvider.getSite(siteId).then((site) => {
             const params = {
                 choiceid: choiceId
@@ -294,7 +303,9 @@ export class AddonModChoiceProvider {
                 preSets.emergencyCache = false;
             }
 
-            return site.read('mod_choice_get_choice_results', params, preSets).then((response) => {
+            return site.read('mod_choice_get_choice_results', params, preSets)
+                    .then((response: AddonModChoiceGetChoiceResults): any => {
+
                 if (response.options) {
                     return response.options;
                 }
@@ -456,3 +467,96 @@ export class AddonModChoiceProvider {
         });
     }
 }
+
+/**
+ * Choice returned by mod_choice_get_choices_by_courses.
+ */
+export type AddonModChoiceChoice = {
+    id: number; // Choice instance id.
+    coursemodule: number; // Course module id.
+    course: number; // Course id.
+    name: string; // Choice name.
+    intro: string; // The choice intro.
+    introformat: number; // Intro format (1 = HTML, 0 = MOODLE, 2 = PLAIN or 4 = MARKDOWN).
+    introfiles?: CoreWSExternalFile[]; // @since 3.2.
+    publish?: boolean; // If choice is published.
+    showresults?: number; // 0 never, 1 after answer, 2 after close, 3 always.
+    display?: number; // Display mode (vertical, horizontal).
+    allowupdate?: boolean; // Allow update.
+    allowmultiple?: boolean; // Allow multiple choices.
+    showunanswered?: boolean; // Show users who not answered yet.
+    includeinactive?: boolean; // Include inactive users.
+    limitanswers?: boolean; // Limit unswers.
+    timeopen?: number; // Date of opening validity.
+    timeclose?: number; // Date of closing validity.
+    showpreview?: boolean; // Show preview before timeopen.
+    timemodified?: number; // Time of last modification.
+    completionsubmit?: boolean; // Completion on user submission.
+    section?: number; // Course section id.
+    visible?: boolean; // Visible.
+    groupmode?: number; // Group mode.
+    groupingid?: number; // Group id.
+};
+
+/**
+ * Option returned by mod_choice_get_choice_options.
+ */
+export type AddonModChoiceOption = {
+    id: number; // Option id.
+    text: string; // Text of the choice.
+    maxanswers: number; // Maximum number of answers.
+    displaylayout: boolean; // True for orizontal, otherwise vertical.
+    countanswers: number; // Number of answers.
+    checked: boolean; // We already answered.
+    disabled: boolean; // Option disabled.
+};
+
+/**
+ * Result returned by mod_choice_get_choice_results.
+ */
+export type AddonModChoiceResult = {
+    id: number; // Choice instance id.
+    text: string; // Text of the choice.
+    maxanswer: number; // Maximum number of answers.
+    userresponses: {
+        userid: number; // User id.
+        fullname: string; // User full name.
+        profileimageurl: string; // Profile user image url.
+        answerid?: number; // Answer id.
+        timemodified?: number; // Time of modification.
+    }[];
+    numberofuser: number; // Number of users answers.
+    percentageamount: number; // Percentage of users answers.
+};
+
+/**
+ * Result of WS mod_choice_get_choices_by_courses.
+ */
+export type AddonModChoiceGetChoicesByCoursesResult = {
+    choices: AddonModChoiceChoice[];
+    warnings?: CoreWSExternalWarning[];
+};
+
+/**
+ * Result of WS mod_choice_get_choice_options.
+ */
+export type AddonModChoiceGetChoiceOptionsResult = {
+    options: AddonModChoiceOption[]; // Options.
+    warnings?: CoreWSExternalWarning[];
+};
+
+/**
+ * Result of WS mod_choice_get_choice_results.
+ */
+export type AddonModChoiceGetChoiceResults = {
+    options: AddonModChoiceResult[];
+    warnings?: CoreWSExternalWarning[];
+};
+
+/**
+ * Result of WS mod_choice_delete_choice_responses.
+ */
+export type AddonModChoiceDeleteChoiceResponsesResult = {
+    status: boolean; // Status, true if everything went right.
+    warnings?: CoreWSExternalWarning[];
+};