Case Study #2 Connecting Klaviyo & Attentive for Seamless Customer Data Integration

Industry: Supplements / Wellness
Services: Data Infrastructure, Signup UX, Cross-Channel Integration
Tools Used: Klaviyo, Attentive, Custom API, Webhooks

The Challenge

The client had two separate systems for email and SMS — Klaviyo for email, Attentive for SMS — and no clear way to connect them. SMS opt-ins were being lost, duplicated, or siloed. Their high-intent traffic was signing up via Klaviyo pop-ups, but mobile numbers weren’t always syncing with Attentive.

This was creating:

Data fragmentation across platforms
Missed opportunities for SMS remarketing
Compliance risks around opt-in confirmation

Our Approach

We started by auditing their current signup UX and backend data flow.

Key steps we took:

Rebuilt the Klaviyo pop-up to collect first name, last name, email, and phone number with SMS opt-in
Implemented hidden fields + conditional logic to ensure data integrity
Collaborated with Attentive to activate a custom API unit for cross-platform sync
Used Klaviyo webhooks to push signup data directly into Attentive in real time
QA-tested opt-in language, checkbox placement, and mobile responsiveness for compliance and conversions