Mäuse
Get the app
PRIVACY

Privacy Policy

Mäuse is local-first. Manual expense tracking stays on your iPhone. The optional Voice Mode sends data to OpenAI only after you explicitly enable it. This policy also explains the privacy-focused analytics used on this website.

Effective: July 12, 2026 · Version 1.0

Who is responsible?

Mäuse is developed and provided by Michael Diestelberg in Germany. For privacy questions or requests, email support@mäuse.app.

1. Manual expense tracking

Expenses you enter manually—including amount, description, date, and split—are stored locally on your device using Apple’s SwiftData framework. Mäuse does not operate an account system or an app backend, and the developer does not receive this information.

You can edit or delete individual expenses in the app. You can also replace all local expenses by importing a backup.

2. Backup and restore

When you export a backup, Mäuse creates a JSON file containing your expense records. You choose where to save or share that file using Apple’s system interface. Mäuse does not upload backups to a developer-operated server. Your OpenAI API key and Voice Mode consent settings are never included in backups.

3. Optional Voice Mode and OpenAI

Voice Mode is disabled by default. Before it can be enabled, Mäuse displays a dedicated disclosure and asks for your explicit consent. Manual entry remains available if you decline.

When you verify an API key, the key is sent directly over HTTPS to OpenAI to request a short-lived Realtime client secret. The API key is stored in Apple Keychain on your device. It is not sent to the Mäuse developer and is not included in backups.

Only while you run a Voice Mode session, Mäuse sends the following directly to OpenAI:

OpenAI returns transcripts, confirmations, and structured expense drafts. Drafts are saved to your local expense database only when you choose to save them.

According to OpenAI’s current API data controls, API content is not used to train OpenAI models unless the API account owner explicitly opts in. For the Realtime API, abuse-monitoring logs may retain customer content for up to 30 days by default, unless longer retention is required by law or needed for safety. See OpenAI’s API data controls and OpenAI’s Privacy Policy.

Voice Mode uses your own OpenAI API project. OpenAI may charge that project for usage. Mäuse does not receive any part of those charges.

Your Voice Mode choices

4. Microphone permission

iOS asks for microphone access the first time Voice Mode needs it. Mäuse accesses the microphone only during an active Voice Mode session. You can revoke microphone access in iOS Settings.

5. App analytics, advertising, and tracking

The Mäuse iPhone app contains no advertising SDK, analytics SDK, telemetry service, or cross-app tracking. It does not use Apple’s advertising identifier.

6. Website hosting and Vercel Web Analytics

The Mäuse website is hosted by Vercel and uses Vercel Web Analytics. Vercel receives technical request information needed to deliver and protect the site. Web Analytics records page views using privacy-focused, aggregated data such as the visited page, referrer, country or region, browser, operating system, and device type.

Vercel states that Web Analytics does not use third-party cookies, does not associate analytics data with an individual or IP address, and uses a request-derived visitor hash that is discarded after 24 hours. See Vercel’s Web Analytics privacy information and Vercel’s Privacy Policy.

The website stores only your language and theme preferences in browser local storage. These preferences stay in your browser until you clear them.

7. Legal bases for processing

Where the EU General Data Protection Regulation applies, Voice Mode data is transmitted on the basis of your consent and at your request to provide the feature. Website delivery, security, and aggregated traffic measurement are based on legitimate interests in operating, protecting, and improving the website.

8. International processing

OpenAI and Vercel may process information outside your country. Their applicable contracts, privacy policies, and transfer safeguards govern that processing. Because Voice Mode uses your own OpenAI project, any project-level data residency or retention settings are controlled by the owner of that OpenAI account.

9. Retention

10. Your rights

Depending on applicable law, you may have rights to access, correct, delete, restrict, or object to processing, and to withdraw consent. You may also complain to your local data protection authority. Most app data is controlled directly by you on your device; the developer cannot retrieve local expenses or your API key.

11. Children

Mäuse is not directed specifically at children and should not be used to send another person’s sensitive information to OpenAI without their permission.

12. Changes to this policy

This policy may be updated when Mäuse, its service providers, or legal requirements change. Material changes to Voice Mode data sharing will require renewed in-app consent.

Contact

Questions about privacy or the app are welcome.

Email privacy support