Last updated: 9 July 2026
Horizon4 is operated by ΧΑΤΖΗΛΑΜΠΡΟΥ ΕΥΑΓΓΕΛΟΣ ΤΟΥ ΜΙΧΑΗΛ (CHATZILAMPROU EUAGGELOS TOU MICHAIL), a Greek sole proprietorship registered with GEMI under number 053376248000, VAT number 076250761, Tax Office of Katerini, with registered address at K. Karamanli 42, Anatolikou Olympou, Dion-Olympos / Pieria, 60065, Greece.
When you sign up, we collect your email address and, if you use Google Sign-In, your Google profile name and avatar. We store the items, notes, and canvas data you create inside the app.
Your data is used solely to provide the Horizon4 service — authenticating you, syncing your canvas across devices, and enabling features you explicitly use. We do not sell, share, or use your data for advertising.
Your data is stored securely in Supabase (PostgreSQL) hosted on AWS infrastructure in the EU region. All data in transit is encrypted via TLS. Data at rest is encrypted by the hosting provider.
We use the following third-party services: Supabase for database and authentication, and Google OAuth as an optional sign-in method. These services have their own privacy policies.
We use a session cookie to keep you logged in. No tracking or analytics cookies are used. We do not use any third-party analytics or advertising scripts.
You can request deletion of your account and all associated data at any time by contacting us. You can also export your data from within the app settings.
No Data Protection Officer is currently appointed. For privacy, data protection, or GDPR-related requests, contact privacy@horizon4.app.
For general inquiries, contact hello@horizon4.app. For support requests, contact support@horizon4.app. For privacy, data protection, or GDPR-related requests, contact privacy@horizon4.app.