the stack app

Privacy Policy

Last updated: January 25, 2026

the stack app ("we," "us," or "our") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, and share information when you use our mobile application and website (collectively, the "Service").

Information We Collect

Information You Provide

  • Phone number: Used to create and verify your account
  • Profile information: Display name, username (handle), and profile photo
  • User-generated content: Items, stacks, photos, descriptions, and reactions you create

Information We Collect Automatically

  • Usage analytics: How you interact with the app, including views, searches, and shares
  • Device information: Device type, operating system, and app version
  • Device tokens: Used to send push notifications (with your permission)

Information from Other Sources

  • Contact list (optional): If you choose to share your contacts, we store hashed phone numbers to help you find friends on the app. We never store your contacts' names or other details.

How We Use Your Information

We use your information to:

  • Create and manage your account
  • Enable you to create, share, and discover stacks and items
  • Connect you with friends and suggest people you may know
  • Send notifications about activity on your account (follows, saves, reactions)
  • Improve and personalize your experience
  • Analyze how the Service is used to make it better
  • Prevent fraud and ensure the security of our Service

AI-Powered Features

We use AI to make adding items easier. When you add an item by name, photo, or link:

  • We use Google's Gemini AI to identify products and extract information like brand, type, and description
  • We may scrape publicly available product pages to find accurate details and images
  • This processing helps auto-fill item details so you don't have to type everything manually

Your photos and item data may be sent to our AI service providers for processing. We do not use your personal content to train AI models.

Third-Party Services

We work with trusted third parties to provide our Service:

  • Supabase: Database, authentication, and file storage
  • Google Gemini: AI-powered item recognition and enrichment
  • Firecrawl: Web scraping for product information
  • Twilio: Phone number verification via SMS
  • Vercel: Website hosting
  • Railway: API hosting

These providers have their own privacy policies and are contractually required to protect your data.

Sharing of Information

We do not sell your personal information. We share information only in these cases:

  • Public content: Stacks and items you make public are visible to other users
  • Your profile: Your display name, handle, and profile photo are visible to other users
  • Service providers: With vendors who help us operate the Service (as described above)
  • Legal requirements: When required by law or to protect rights and safety
  • Business transfers: In connection with a merger, acquisition, or sale of assets

Data Retention

We keep your information for as long as your account is active or as needed to provide the Service.

  • If you delete your account, we will delete your personal data within 30 days
  • Some information may be retained longer for legal compliance or to resolve disputes
  • Anonymized analytics data may be kept indefinitely
  • Content you contributed to the public item library may remain after account deletion

Your Rights and Choices

You have control over your data:

  • Access: You can view your data in the app at any time
  • Correction: You can update your profile and content directly in the app
  • Deletion: You can delete individual items, stacks, or your entire account
  • Export: Contact us to request a copy of your data
  • Notifications: You can disable push notifications in your device settings
  • Contacts: You can choose not to share your contacts, or revoke access later

California Privacy Rights (CCPA)

If you are a California resident, you have additional rights:

  • Right to know what personal information we collect and how we use it
  • Right to delete your personal information
  • Right to opt-out of the sale of personal information (we do not sell your data)
  • Right to non-discrimination for exercising your privacy rights

To exercise these rights, contact us at willsepesi@gmail.com

European Privacy Rights (GDPR)

If you are in the European Economic Area, you have rights under the GDPR including:

  • Right to access, correct, or delete your personal data
  • Right to restrict or object to processing
  • Right to data portability
  • Right to withdraw consent
  • Right to lodge a complaint with a supervisory authority

Our legal basis for processing is your consent (for contacts and notifications), contract performance (for providing the Service), and legitimate interests (for analytics and security).

Security

We use industry-standard security measures to protect your data, including encryption in transit and at rest, secure authentication, and access controls. However, no system is completely secure, and we cannot guarantee absolute security.

Children's Privacy

the stack app is not intended for children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal information, please contact us so we can delete it.

Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of significant changes by posting a notice in the app or sending you a notification. Your continued use of the Service after changes become effective means you accept the updated policy.

Contact Us

If you have questions about this Privacy Policy or want to exercise your privacy rights, please contact us at:

willsepesi@gmail.com