Effective Date: February 10, 2026
Stacks is built by Red Collar. This policy explains how we collect, use, and protect your information.
When you sign in with Google or Apple, we collect your email address and display name for account identification.
We store the stacks, items, descriptions, and images you create. Public stacks are visible to other users and on share links.
We collect anonymized usage data (screens viewed, features used) to improve the app. This data is not tied to your personal identity.
If you enable push notifications, we store your device token to deliver notifications about activity on your account (new followers, stack saves, taste matches).
Stacks computes taste similarity scores by comparing the items in your stacks with other users' items using Jaccard similarity. This is done server-side. Your taste scores are only visible to you and the matched user.
Stacks may include affiliate links in product listings. Clicking these links may share referral data with the merchant. This does not share your Stacks account data. Affiliate relationships do not influence taste matching or content recommendations.
Your data is stored on secure servers hosted on Railway.app with PostgreSQL databases. All data is transmitted over HTTPS. We do not sell your personal data to third parties.
Stacks is not directed at children under 13. We do not knowingly collect personal information from children.
Your data is retained while your account is active. You can delete your account and all associated data at any time through the app's settings. We process deletion requests within 30 days.
You may:
We may update this policy from time to time. Significant changes will be communicated through the app.
Questions about this policy? Contact us at stacks@redcollar.io.