diff --git a/scripts/langindex.json b/scripts/langindex.json
index 2c1ca2a62..8bd92d9cc 100644
--- a/scripts/langindex.json
+++ b/scripts/langindex.json
@@ -1828,6 +1828,7 @@
   "core.login.selectacountry": "moodle",
   "core.login.selectsite": "local_moodlemobileapp",
   "core.login.signupplugindisabled": "local_moodlemobileapp",
+  "core.login.signuprequiredfieldnotsupported": "local_moodlemobileapp",
   "core.login.siteaddress": "local_moodlemobileapp",
   "core.login.sitehasredirect": "local_moodlemobileapp",
   "core.login.siteinmaintenance": "local_moodlemobileapp",
diff --git a/src/assets/lang/en.json b/src/assets/lang/en.json
index f3f916c98..dfc6fd17d 100644
--- a/src/assets/lang/en.json
+++ b/src/assets/lang/en.json
@@ -1828,6 +1828,7 @@
     "core.login.selectacountry": "Select a country",
     "core.login.selectsite": "Please select your site:",
     "core.login.signupplugindisabled": "{{$a}} is not enabled.",
+    "core.login.signuprequiredfieldnotsupported": "The signup form contains a required custom field that isn't supported in the app. Please create your account using a web browser.",
     "core.login.siteaddress": "Your site",
     "core.login.sitehasredirect": "Your site contains at least one HTTP redirect. The app cannot follow redirects, this could be the issue that's preventing the app from connecting to your site.",
     "core.login.siteinmaintenance": "Your site is in maintenance mode",
diff --git a/src/core/login/lang/en.json b/src/core/login/lang/en.json
index c0003e51b..fb28b87c2 100644
--- a/src/core/login/lang/en.json
+++ b/src/core/login/lang/en.json
@@ -102,6 +102,7 @@
     "selectacountry": "Select a country",
     "selectsite": "Please select your site:",
     "signupplugindisabled": "{{$a}} is not enabled.",
+    "signuprequiredfieldnotsupported": "The signup form contains a required custom field that isn't supported in the app. Please create your account using a web browser.",
     "siteaddress": "Your site",
     "sitehasredirect": "Your site contains at least one HTTP redirect. The app cannot follow redirects, this could be the issue that's preventing the app from connecting to your site.",
     "siteinmaintenance": "Your site is in maintenance mode",
diff --git a/src/core/login/pages/email-signup/email-signup.html b/src/core/login/pages/email-signup/email-signup.html
index 3e52b4b6c..fd8a226e4 100644
--- a/src/core/login/pages/email-signup/email-signup.html
+++ b/src/core/login/pages/email-signup/email-signup.html
@@ -16,8 +16,20 @@
 
     <core-loading [hideUntil]="settingsLoaded" *ngIf="!isMinor">
 
+        <!-- Site has an unsupported required field. -->
+        <ion-list *ngIf="!allRequiredSupported">
+            <ion-item text-wrap>
+                {{ 'core.login.signuprequiredfieldnotsupported' | translate }}
+            </ion-item>
+            <ion-item>
+                <a ion-button block [href]="signupUrl" core-link [autoLogin]="no">
+                    {{ 'core.openinbrowser' | translate }}
+                </a>
+            </ion-item>
+        </ion-list>
+
         <!-- Age verification. -->
-        <form ion-list *ngIf="settingsLoaded && settings && ageDigitalConsentVerification" [formGroup]="ageVerificationForm" (ngSubmit)="verifyAge($event)" #ageForm>
+        <form ion-list *ngIf="allRequiredSupported && settingsLoaded && settings && ageDigitalConsentVerification" [formGroup]="ageVerificationForm" (ngSubmit)="verifyAge($event)" #ageForm>
             <ion-item-divider text-wrap>
                 <p class="item-heading">{{ 'core.agelocationverification' | translate }}</p>
             </ion-item-divider>
@@ -47,7 +59,7 @@
         </form>
 
         <!-- Signup form. -->
-        <form ion-list *ngIf="settingsLoaded && settings && !ageDigitalConsentVerification" [formGroup]="signupForm" (ngSubmit)="create($event)" #signupFormEl>
+        <form ion-list *ngIf="allRequiredSupported && settingsLoaded && settings && !ageDigitalConsentVerification" [formGroup]="signupForm" (ngSubmit)="create($event)" #signupFormEl>
             <ion-item text-wrap text-center>
                 <!-- If no sitename show big siteurl. -->
                 <p *ngIf="!siteName" padding class="item-heading">{{siteUrl}}</p>
@@ -143,7 +155,7 @@
         </form>
     </core-loading>
 
-    <ion-list *ngIf="isMinor">
+    <ion-list *ngIf="allRequiredSupported && isMinor">
         <ion-item-divider text-wrap>
             <p *ngIf="siteName" class="item-heading padding"><core-format-text [text]="siteName" [filter]="false"></core-format-text></p>
         </ion-item-divider>
diff --git a/src/core/login/pages/email-signup/email-signup.ts b/src/core/login/pages/email-signup/email-signup.ts
index fc0eb808d..496ddc269 100644
--- a/src/core/login/pages/email-signup/email-signup.ts
+++ b/src/core/login/pages/email-signup/email-signup.ts
@@ -48,6 +48,8 @@ export class CoreLoginEmailSignupPage {
     countries: any;
     categories: any[];
     settingsLoaded = false;
+    allRequiredSupported = true;
+    signupUrl: string;
     captcha = {
         recaptcharesponse: ''
     };
@@ -136,63 +138,70 @@ export class CoreLoginEmailSignupPage {
     }
 
     /**
-     * Fetch the required data from the server-
+     * Fetch the required data from the server.
+     *
+     * @return Promise resolved when done.
      */
-    protected fetchData(): Promise<any> {
-        // Get site config.
-        return this.sitesProvider.getSitePublicConfig(this.siteUrl).then((config) => {
-            this.siteConfig = config;
+    protected async fetchData(): Promise<void> {
+        try {
+            // Get site config.
+            this.siteConfig = await this.sitesProvider.getSitePublicConfig(this.siteUrl);
+            this.signupUrl = this.textUtils.concatenatePaths(this.siteConfig.httpswwwroot, 'login/signup.php');
 
-            if (this.treatSiteConfig(config)) {
+            if (this.treatSiteConfig(this.siteConfig)) {
                 // Check content verification.
                 if (typeof this.ageDigitalConsentVerification == 'undefined') {
-                    return this.wsProvider.callAjax('core_auth_is_age_digital_consent_verification_enabled', {},
-                            {siteUrl: this.siteUrl }).then((result) => {
 
-                        this.ageDigitalConsentVerification = result.status;
-                    }).catch((e) => {
-                        // Capture exceptions, fail silently.
-                    }).then(() => {
-                        return this.getSignupSettings();
-                    });
-                } else {
-                    return this.getSignupSettings();
+                    const result = await this.utils.ignoreErrors(this.wsProvider.callAjax(
+                            'core_auth_is_age_digital_consent_verification_enabled', {}, {siteUrl: this.siteUrl }));
+
+                    this.ageDigitalConsentVerification = result && result.status;
                 }
+
+                await this.getSignupSettings();
             }
-        }).then(() => {
+
             this.completeFormGroup();
-        }).catch((err) => {
-            this.domUtils.showErrorModal(err);
-        });
+        } catch (error) {
+            if (this.allRequiredSupported) {
+                this.domUtils.showErrorModal(error);
+            }
+        }
     }
 
     /**
      * Get signup settings from server.
+     *
+     * @return Promise resolved when done.
      */
-    protected getSignupSettings(): Promise<any> {
-        return this.wsProvider.callAjax('auth_email_get_signup_settings', {}, { siteUrl: this.siteUrl }).then((settings) => {
-            this.settings = settings;
-            this.categories = this.loginHelper.formatProfileFieldsForSignup(settings.profilefields);
+    protected async getSignupSettings(): Promise<void> {
+        const settings = await this.wsProvider.callAjax('auth_email_get_signup_settings', {}, { siteUrl: this.siteUrl });
 
-            if (this.settings.recaptchapublickey) {
-                this.captcha.recaptcharesponse = ''; // Reset captcha.
-            }
+        if (this.userProfileFieldDelegate.hasRequiredUnsupportedField(settings.profilefields)) {
+            this.allRequiredSupported = false;
 
-            if (!this.countryControl.value) {
-                this.countryControl.setValue(settings.country || '');
-            }
+            throw new Error(this.translate.instant('core.login.signuprequiredfieldnotsupported'));
+        }
 
-            this.namefieldsErrors = {};
-            if (settings.namefields) {
-                settings.namefields.forEach((field) => {
-                    this.namefieldsErrors[field] = this.loginHelper.getErrorMessages('core.login.missing' + field);
-                });
-            }
+        this.settings = settings;
+        this.categories = this.loginHelper.formatProfileFieldsForSignup(settings.profilefields);
 
-            return this.utils.getCountryListSorted().then((countries) => {
-                this.countries = countries;
+        if (this.settings.recaptchapublickey) {
+            this.captcha.recaptcharesponse = ''; // Reset captcha.
+        }
+
+        if (!this.countryControl.value) {
+            this.countryControl.setValue(settings.country || '');
+        }
+
+        this.namefieldsErrors = {};
+        if (settings.namefields) {
+            settings.namefields.forEach((field) => {
+                this.namefieldsErrors[field] = this.loginHelper.getErrorMessages('core.login.missing' + field);
             });
-        });
+        }
+
+        this.countries = await this.utils.getCountryListSorted();
     }
 
     /**
diff --git a/src/core/user/providers/user-profile-field-delegate.ts b/src/core/user/providers/user-profile-field-delegate.ts
index 4acef8d5e..e48879eb1 100644
--- a/src/core/user/providers/user-profile-field-delegate.ts
+++ b/src/core/user/providers/user-profile-field-delegate.ts
@@ -157,4 +157,20 @@ export class CoreUserProfileFieldDelegate extends CoreDelegate {
             return result;
         });
     }
+
+    /**
+     * Check if any of the profile fields is not supported in the app.
+     *
+     * @param fields List of fields.
+     * @return Whether any of the profile fields is not supported in the app.
+     */
+    hasRequiredUnsupportedField(fields: any[]): boolean {
+        if (!fields || !fields.length) {
+            return false;
+        }
+
+        return fields.some((field) => {
+            return field.required && !this.hasHandler(field.type || field.datatype);
+        });
+    }
 }
diff --git a/src/providers/utils/utils.ts b/src/providers/utils/utils.ts
index 8ee4a2798..92baac78d 100644
--- a/src/providers/utils/utils.ts
+++ b/src/providers/utils/utils.ts
@@ -1576,6 +1576,22 @@ export class CoreUtilsProvider {
 
         delete this.qrScanData;
     }
+
+    /**
+     * Ignore errors from a promise.
+     *
+     * @param promise Promise to ignore errors.
+     * @return Promise with ignored errors.
+     */
+    async ignoreErrors<T>(promise: Promise<T>): Promise<T | undefined> {
+        try {
+            const result = await promise;
+
+            return result;
+        } catch (error) {
+            // Ignore errors.
+        }
+    }
 }
 
 export class CoreUtils extends makeSingleton(CoreUtilsProvider) {}