Amplitude on your landing pages
Amplitude is where many product teams decide what's working. LanderLab's webhook makes sure paid acquisition is part of that decision. Each lead is posted to Amplitude's HTTP V2 API as an event, with the form's answers as event properties, the person's details as user properties, and the visitor's IP and browser so location and device describe the person, not a server.
It's for teams that buy traffic and judge it on behavior: subscription apps, SaaS trials, marketplaces. When the lead event and the product events share a user ID, a behavioral cohort can start with "came from this campaign".
Landing page leads as Amplitude events
Each submit becomes a "Lead Submitted" event in Amplitude, with the quiz answers and form fields as event properties. The webhook's JSON mode builds the events array Amplitude's HTTP V2 API expects, and Amplitude's API key, which it treats as a public key, travels in the request body. The Secret Key never leaves your Amplitude account.
Use the person's email or your product's user ID as the user_id. Amplitude asks for IDs of at least five characters, which an email always is.
Behavioral cohorts by campaign and variant
With utm_campaign, utm_source and the A/B variant on the lead event, any chart can be split by the ad that started it. Build a cohort of users from your best TikTok campaign and compare their retention with the Google search cohort, or check whether the variant that won on leads also wins on second-week activity.
User properties that follow the person
User properties sent with the lead stay on the user: the email, the plan they said they wanted, the budget band from the quiz. Every later event inherits them, so a funnel two months from now can still be split by an answer the person gave on the landing page.
Location and device from the visitor, not the server
An event sent from a server would place every lead in the server's city. LanderLab sends the visitor's IP and user agent with each lead, Amplitude reads them, and your country, region and device reports stay true for paid traffic.
Clean data in, with Workflows
Product analytics is only as good as what goes in. Put a Workflow between your pages and Amplitude and the HTTP Request node can send only the leads that count: finished quizzes, real geos, no internal tests. The Runs view shows every lead's path and any step that failed.
