Privacy Policy

ZenSpend — expense tracking application
Publisher: Lux Corp Sp. z o.o., ul. Zwycięstwa 3, 44-292 Zwonowice, Poland

Last updated: April 5, 2026

1. Data We Collect

ZenSpend does not collect, transmit, or store any personal data on external servers. All data (transactions, categories, investments, settings) is stored exclusively on your device in an encrypted local database.

2. Camera

The app uses the device camera only for scanning receipts. A receipt photo is:

• taken only after the user explicitly taps the "Scan Receipt" button,
• processed depending on the selected AI model:
  • OpenAI (cloud) — the image is sent to the OpenAI API for text recognition (OCR),
  • Gemma (on-device) — the image is processed entirely on the device by Google Gemma 4 E4B (LiteRT-LM); no data leaves the device,
• never saved to the device or anywhere else,
• never shared with any third party other than OpenAI (only when OpenAI mode is selected; see section 3).

The camera permission (android.permission.CAMERA) is required only if the user chooses to use the AI receipt scanning feature. All other app features work normally without this permission.

3. AI Models for Receipt Scanning

The app offers two AI modes for receipt scanning:

3a. OpenAI (Cloud Mode)

If the user selects the OpenAI model, the receipt image is sent to the OpenAI API (OpenAI Privacy Policy) for content recognition. The transmission is encrypted via HTTPS.

• The OpenAI API key is provided by the user and stored locally in encrypted device storage (EncryptedSharedPreferences).
• Lux Corp Sp. z o.o. has no access to the user's API key.
• No other data (transactions, categories, settings) is sent to OpenAI or any other server.

3b. Gemma (On-Device Mode, No Internet Required)

If the user selects the Gemma model, all processing happens entirely on the device using Google Gemma 4 E4B running via LiteRT-LM. No receipt data is sent to any external server.

• The Gemma model (~3.7 GB) is downloaded once from Hugging Face and stored locally on the device.
• After the model is downloaded, receipt scanning works completely offline.
• Lux Corp Sp. z o.o. has no access to data processed by the Gemma model.

4. Data Storage

• Database — transaction, category, and investment data is stored locally in a Room (SQLite) database on the device.
• Settings — API key, currency, language, and AI model are stored in EncryptedSharedPreferences with AES-256 encryption.
• The app does not use any analytics, tracking, or advertising services.

5. Data Sharing

We do not share, sell, or transfer any user data to third parties. The only exception is the voluntary transmission of a receipt photo to the OpenAI API (described in section 3).

6. App Permissions

7. Security

We apply the following security measures:

• Sensitive data is encrypted (AES-256-GCM / AES-256-SIV) using AndroidX Security / EncryptedSharedPreferences.
• Communication with the OpenAI API uses HTTPS only.
• Minimal permissions — the app does not require access to contacts, location, microphone, or device storage.

8. Your Rights

Since all data is stored locally on your device, you have full control over your data. To delete all data, simply uninstall the app or clear the app's data in Android system settings.

9. Children

This app is not directed at children under the age of 13 and does not knowingly collect data from children.

10. Changes to This Privacy Policy

We will notify users of any significant changes to this privacy policy by updating the date at the top of this document. We recommend checking this page periodically.

11. Contact

For any privacy-related questions, please contact us:

Lux Corp Sp. z o.o.
ul. Zwycięstwa 3, 44-292 Zwonowice, Poland
Email: kontakt@luxcorp.pl
Website: https://it.luxcorp.pl