TillKit UK Postcode Rules lets a Shopify store block or change checkout and delivery options by postcode. This page says what the app stores and why.
The app keeps no customer data. Postcodes and carts are read only inside Shopify's checkout, by Shopify Functions that run on Shopify's servers and keep nothing. No orders, addresses or payment details reach the app. Shopify's customer data request and customer deletion notices, which carry a customer's id, email and phone number, are acknowledged and dropped without being stored, as there is nothing held to return or delete.
Nothing is sold or shared. The app uses Cloudflare to host its pages and its session database, and Shopify to run the checkout functions. Cloudflare keeps request logs (the page address and the store's domain) for its standard retention period.
Uninstalling the app deletes the store's sessions straight away. Shopify's shop data deletion request deletes them too. The rules live in the store's own Shopify data, and the app keeps no copy of them.
Questions about this policy: hello@tillkit.app.