Privacy & Transparency

How your words are handled.

Carmen is built around your voice. That means being honest about what happens to it.

Last updated: April 2026

The short version Your songs belong to you. We collect what’s needed to run the app, nothing more. We don’t sell your data, and we don’t train AI on your writing. If you delete your account, your content goes with it.

What we collect

Account information

When you sign in with Google, we receive your name, email address, and profile photo. We don’t ever see or store your Google password. Authentication is handled by Firebase Authentication.

Your songs and lyrics

Everything you write in Carmen — song titles, lyrics, section structures, notes, metadata (key, tempo, mood) — is stored in Firebase Firestore under your user ID. Only you can access it through the app.

Voice profiles

Your voice profiles include your writing style choices from onboarding and writing samples captured from your lyrics. Samples are only used to teach Carmen your personal style — they never leave your profile and are never used to train general AI models.

Preferences and settings

Your theme choice, language, layout preferences, and plan tier (Free, Creator, or Pro) are stored alongside your account.

Usage data

We track how many AI generations you’ve used each month to enforce plan limits. We don’t track individual tool usage, browsing patterns, or analytics beyond this counter.

Payment information

When you subscribe to Creator or Pro, your payment details are handled entirely by Stripe. Carmen never sees or stores your credit card number. We only receive a confirmation that your payment succeeded, and your Stripe customer ID for subscription management.

Feedback you submit

If you send feedback through the in-app form, we capture your message along with context (current song ID, plan, browser info) to help us understand and act on it. Feedback is only visible to the developer.

How we use it

To run the app

Your songs, profiles, and preferences are used to provide the writing experience. They sync across your devices when you sign in.

To help you write

When you use an AI tool, we send the relevant context (the line you selected, surrounding lyrics, your section name, your voice profile traits) to Anthropic’s Claude API. Anthropic returns suggestions that we show you. Per Anthropic’s standard API policy, they retain prompts for up to 30 days for abuse monitoring, and they do not train their models on API traffic.

To improve the app

Your feedback submissions help us fix bugs and prioritise features. We do not analyse your lyrics or writing patterns for product decisions.

Who has access

You

Through the Carmen app, signed in with your account. Nobody else using Carmen can see your content — Firestore security rules make that impossible.

The developer (me)

I’m the sole developer of Carmen. As the Firebase project owner, I technically have admin access to the database through the Firebase Console. I do not read user content. I may look at aggregate data (number of users, total songs, feedback submissions) and at your specific account if you contact me for support. I will never share, publish, or use your lyrics for any purpose.

Third parties we use

What we never do Sell your data. Share it with advertisers. Use your lyrics to train AI models. Publish your songs. Give any other Carmen user access to your account. Contact you with marketing spam.

Your rights

Access and export

You can export any song as plain text, Markdown, or PDF directly from the app. If you need a full export of all your data, email me and I’ll send it to you.

Deletion

You can delete individual songs from within the app at any time. To delete your entire account and all associated data (songs, voice profiles, preferences, feedback), email me. Account deletion is permanent and removes everything from Firestore within 24 hours.

Correction

You can edit your voice profile, songs, and preferences at any time from within the app.

Withdraw consent

You can stop using Carmen and request deletion at any time. Paid subscriptions can be cancelled from within the app — you’ll retain access until the end of your billing period, then drop to the free tier.

Data security

All data transfers are encrypted in transit (HTTPS). Firebase Firestore encrypts data at rest. Access to your account requires authentication via Google. Firestore security rules prevent any authenticated user from accessing anyone else’s data. AI generation endpoints require a valid authentication token.

No system is perfectly secure. If you have concerns about storing particularly sensitive or confidential content in Carmen, please use your judgement — the same way you would with any cloud service.

Data retention

We keep your data for as long as your account exists. When you delete your account, everything is removed from our active database within 24 hours. Backups are automatically purged within 30 days. Anthropic retains AI prompts for up to 30 days per their own policy, then deletes them.

Children’s privacy

Carmen is not intended for children under 13. We do not knowingly collect personal information from anyone under 13. If you believe a child has created an account, please contact me and I’ll remove it.

Changes to this policy

If we make material changes to how data is collected or used, we’ll update this page and notify active users in the app. Minor clarifications will be updated here without notice. The “last updated” date at the top always reflects the latest revision.

Contact

Questions, concerns, data requests, or account deletion — reach out through the in-app feedback form, or email the developer directly. Carmen is a small, independent project, and real humans respond.

A final note Carmen exists because songs deserve better tools. The relationship between a writer and their work is sacred. We take that seriously. If there’s anything about this policy you find unclear, unfair, or insufficient — tell us. We’ll fix it.