Privacy Policy
Effective Date: August 23, 2026 • Last Updated: August 23, 2026 • App: Efzin (iOS) • Developer: Plenum (gr.plenum.efzin)
1 Introduction & Core Privacy Philosophy
Welcome to Efzin (“the App”, “we”, “our”, or “us”), a mobile application developed and published by Plenum (“Plenum Studio”). Efzin is designed to be your privacy-centric life-admin and personal finance companion, providing reminders, budget management, AI receipt processing, multi-inbox email candidate discovery, and user-private cloud backups.
Our guiding principle is simple: your life admin and personal financial data belong exclusively to you. Efzin contains no advertising trackers, sells no data to brokers or advertisers, and stores your operational life records locally on your device with complete encryption and in your private Apple iCloud database.
2 App Store Data Types & Usage
In accordance with Apple App Store Guideline 5.1 and App Store Connect disclosures, here is how Efzin uses and categorizes information:
| Data Type | Linked to User | Used for Tracking | Purpose & Description |
|---|---|---|---|
| Name & Email Address | Yes | No | Account identity from Plenum SSO or Sign in with Apple, and connected email provider accounts. |
| User ID | Yes | No | Efzin internal identifier and linked identity provider tokens. |
| Emails & Receipts | Yes | No | User-selected or opt-in email receipt scanning from connected inboxes. |
| Purchase & Financial Info | Yes | No | Expenses, monthly budgets, subscriptions, imported bank statements, and receipt line items. |
| Photos & Documents | Yes | No | Receipt photos captured via camera/photo picker or PDF invoices imported for OCR extraction. |
| Life Records | Yes | No | Reminders for warranties, vehicles, taxes, returns, prescriptions, and subscriptions. |
3 Where Data Resides & Production Data Flow
A. On-Device Local Storage
All your reminders, expense logs, budget caps, pending review queues, and attached receipt assets are saved in redundant, versioned Application Support files written atomically with complete iOS file protection (NSFileProtectionComplete). Your Google AI Studio API key and session credentials are kept in the hardware-backed iOS Keychain with kSecAttrAccessibleWhenUnlockedThisDeviceOnly.
B. User's Private iCloud Database (CloudKit)
If iCloud Backup is enabled, Efzin serializes your Life items, expenses, and receipt images directly into your private CloudKit container (iCloud.gr.plenum.efzin). This private database is managed by Apple under your personal Apple ID. Plenum servers and workers cannot read, query, or access your private CloudKit database.
C. Efzin Worker & D1 Database
The Efzin API Worker stores only minimal, necessary authentication state: account identities, SHA-256 hashed session digests, AES-256-GCM encrypted provider credentials, and bounded candidate email metadata (sender, subject, date). Full email message bodies, statement files, and receipt images are never persisted in the Efzin backend database.
D. Google Gemini AI Processing
Receipt OCR and document extraction use direct HTTPS connections from your device to Google Gemini (gemini-3.5-flash-lite). Documents are capped at 12 MB. Google processes inputs statelessly according to Google AI Studio Terms, and extracts merchant name, date, and items without saving training copies.
4 Connected Providers (Gmail, Outlook, IMAP, Banks)
- Strict 30-Day Email Discovery: Efzin limits provider queries (Gmail API, Microsoft Graph, IMAP) to messages received within the preceding 30 days.
- Opt-In & Mandatory Approval: Automatic scanning applies only to future candidates received after opt-in. All extracted receipts enter a mandatory review sheet before any expense is committed.
- Provider Disconnection: You can disconnect individual email or bank integrations at any time from Settings, which deletes the corresponding encrypted credentials from the server.
- Bank Statements: CSV, OFX, and statement PDFs are parsed on device. Direct Open Banking integrations (e.g. bunq, Revolut) operate with read-only transaction review workflows.
5 Data Retention & Complete Account Deletion
Efzin provides an instant Delete Efzin Account feature accessible from Settings. Executing account deletion immediately:
- Deletes your server identity, sessions, encrypted email/bank credentials, and candidate metadata in one atomic database batch.
- Clears local Keychain credentials and revokes authentication tokens with Plenum / Apple.
- Wipes all local LifeStore files, pending review queues, and cached receipts from your device.
- Removes your backup manifest and deletes all receipt records from your private CloudKit container.
6 Your GDPR & Privacy Rights
Under European Union General Data Protection Regulation (GDPR) and global privacy regulations, you have the right to access, rectify, port, and erase your personal data. Because Efzin operates with local-first and private CloudKit architectures, you retain direct custody of your files at all times.
If you have questions about our privacy practices, please contact our Data Protection Officer at:
support@plenum.gr • Plenum Studio, Athens, Greece.