Zuddl adds custom registration validations and embedded apps in webinars

Zuddl listed four December 2025 updates on its product updates page and described them in a December Product Pulse post. Organizers can configure validations once at the organization level and apply them to forms in any event's registration flow. Webinars gained a Custom Apps option for embedded third-party tools. Calendar blocks can be customized with merge tags. Field slugs became editable before publishing and locked afterward, with mandatory fields keeping fixed IDs.

The details

• Email validation providers named are ZeroBounce, Kickbox and NeverBounce.
• Validations run server-side and support custom scripts, API logic and custom error messages.
• Zuddl said validations were behind a feature flag for internal and Riskified organizations at the time.
• Custom Apps embeds third-party iframes in the webinar engagement panel.
• Field IDs lock after publish and must be unique across an event, up to 100 characters.

Context

Zuddl released an Open API and email domain restrictions for registration in late 2025. In January 2026 it introduced Sidekick and Ask Zuddl AI agents and added session-level calendar invites, which built on the calendar merge tags here. In March 2026 it automated on-demand webinar pages, and in April 2026 it added file upload fields to registration forms.

Not disclosed

• When form validations became generally available.
• Whether validation provider costs are billed by Zuddl or the provider.
• Which plans include Custom Apps.