Privacy policy

Last updated: 18 October 2026

Winback Lift is a Shopify app published by Elektraset, s.r.o. ("we", "us"). This policy explains what data the app processes when a merchant installs it, why, and how long we keep it. Contact: help@elektraset.com · https://elektraset.com/.

Roles

The merchant who installs Winback Lift is the controller of their customers' personal data. We process that data on the merchant's behalf, only to provide the app's functions, and only on the merchant's instructions (these terms and the app settings).

What the app reads from Shopify

With the access the merchant grants at installation (read orders, customers, products and inventory):

• Orders of the last two years (or the last 60 days until Shopify grants access to older orders): order ID and name, processing and cancellation date, financial status, subtotal after discounts and refunds, currency, discount codes, and the products, quantities, line amounts and unit costs.
• Customers who placed those orders: customer ID, first name, email address, email marketing consent state and tags.
• Store details: shop name, currency, and whether it is a development store; the app's subscription state.

The app does not read payment details, addresses, phone numbers or browsing data, and it never changes store data.

What the app reads from Klaviyo (only if the merchant connects it)

With the merchant's private API key: the names and IDs of Klaviyo message metrics, and "Received", "Opened" and "Clicked" email/SMS events with the email address of the profile, to detect holdout contamination and recent engagement.

What the app sends to Klaviyo (only if the merchant connects it)

For each holdout test, the email address and first name of every customer in the frozen cohort, with the profile properties winback_lift_test, winback_lift_test_id, winback_lift_group (treatment or holdout) and winback_lift_score, added to two lists that the app creates in the merchant's Klaviyo account. The app never changes marketing consent, never subscribes or unsubscribes anyone, and never sends messages.

What the app sends to Shopify Flow (only if the merchant clicks "Send groups to Shopify Flow")

For each customer of a frozen test: the Shopify customer ID, the test name, the group (treatment or holdout), the recoverability score and the planned end date, to the merchant's own Shopify Flow workflows in the same store.

Why

• To compute product reorder windows, recoverability segments and historical-return benchmarks.
• To freeze test cohorts, assign treatment and holdout groups at random, and report incremental purchases, revenue and gross margin.
• To check that holdout customers were not messaged.
• To bill the subscription through Shopify and to count, in aggregate only, how many stores install, use and pay for the app.

We do not sell personal data, use it for advertising, combine it across merchants, or use it to train models.

Storage and security

• Data is stored in a database on our own application server. Email addresses, first names and the Klaviyo key are encrypted at rest (AES-256-GCM); connections use HTTPS.
• Access to the server is limited to the staff who operate the app.
• Test and production data are kept separate.

Retention and deletion

While the app is installed, a daily job deletes:

• orders older than 2 years (the app's analysis window);
• ended holdout tests (with their groups and log) 24 months after the test ended;
• customer records that no longer have any order or test membership in the app;
• customer data requests 30 days after the merchant downloaded the export.

• When the merchant uninstalls the app, we stop processing, delete the Klaviyo key and the access tokens, and end running tests. Shopify then sends a shop deletion request (48 hours after uninstalling) and we delete all data of the store.
• When Shopify forwards a customer's deletion request (customers/redact), we delete that customer's record, orders and test memberships.
• When Shopify forwards a customer's data request (customers/data_request), the app stores the request and shows it to the merchant on its Privacy requests page with a 30-day due date; the merchant downloads a complete export of everything the app holds about that customer (email, first name, consent, tags, orders, holdout tests and where the customer was sent) and passes it on.
• Lists and profiles that the app created in Klaviyo belong to the merchant's Klaviyo account; the merchant can delete them there.

Sub-processors

• Shopify (the platform and billing).
• Klaviyo, only if the merchant connects it, as the merchant's own provider.
• Our hosting provider for the application server.

Your rights

Shoppers should contact the merchant (the store they bought from) to exercise their rights. Merchants can contact us at help@elektraset.com for access, correction or deletion of data we hold for them. You may also complain to a data protection authority; ours is the Slovak Office for Personal Data Protection.

Changes

We will post changes on this page and update the date above.