Legal

Privacy Policy

Undertone reads private conversations. That only works if we are precise about what leaves your phone, who touches it, and what is kept. This page is that description, in plain language.

Effective: July 20, 2026  ·  Last updated: July 20, 2026

The short version. Undertone has no accounts, no ads, no analytics SDKs, and no tracking. We never ask for your name, email, or phone number. When you run an analysis, the conversation text is sent — with both participants' names replaced by "Person A" and "Person B" — to our analysis service and on to an AI provider. Our own service writes it nowhere: no database, no files, no logs. We do not train any model on your conversations and we never sell or rent them.

1. Who we are

Undertone is made by Fernix LLC, a limited liability company organized in the State of New Mexico, United States ("Undertone", "we", "us"). For privacy law that assigns roles, Fernix LLC is the controller of the data described here.

Questions, requests, or complaints: furkankar6@icloud.com.

2. There is no account

Undertone has no sign-up, no login, and no profile. We do not collect your name, email address, phone number, date of birth, contacts, photos, location, or any government identifier. There is nothing for us to look you up by, because we never create a record of you in the first place.

3. What is sent when you run an analysis

Nothing leaves your phone until you have read the consent screen and tapped to continue. If you decline, the analysis does not run and nothing is transmitted. When you do continue, this is the complete payload:

Name replacement is a meaningful reduction, but it is not anonymization. A conversation can still identify people through its content — places, events, nicknames, or details only two people would know. Please keep that in mind when deciding what to analyze.

4. What is never sent, and what the app cannot see

• No images. Undertone has no photo picker, no camera access, and no screenshot or OCR feature. It cannot read images, because it never receives any.
• No contacts, location, microphone, or calendar. The app requests none of these permissions.
• No advertising identifier and no tracking. There is no IDFA, no App Tracking Transparency prompt, and no cross-app or cross-site tracking of any kind.
• No analytics or crash-reporting SDK. No PostHog, Firebase, Amplitude, Sentry, Mixpanel, or equivalent is present in the app.
• No attachments or media files from your chat export.

5. Where your conversation actually goes

Many apps say "sent to AI" and leave it there. Here is the full path, hop by hop:

1. Your phone → our analysis service. Over HTTPS to an endpoint we run on Vercel's serverless platform.
2. Our service → OpenRouter. OpenRouter is the gateway we use to reach large language models.
3. OpenRouter → the model provider. OpenRouter routes the request to the model we have configured. Today that is OpenAI's GPT-4o mini. This is a configuration value, so it may change; when it does, this page is updated.
4. The result comes back along the same path and is displayed on your phone.

6. What is kept, and by whom

Our analysis service keeps nothing. It has no database, no file storage, and no cache, and it does not log conversation content. Your text exists only in the memory of a single function invocation, for the seconds that request takes, and is gone when the request ends. There is no deletion schedule because there is nothing to delete.

We want to be straight with you about the parts we do not control:

• Vercel operates the servers our function runs on and keeps its own operational and invocation logs under its privacy policy.
• OpenRouter and the model provider receive the conversation text in order to produce the analysis. Their retention is governed by their own policies and our account settings with them, not by code in our app. We do not use your conversations to train models, and we do not permit our providers to use them to train theirs — but we can describe our own systems with certainty in a way we cannot describe someone else's.

We never sell, rent, or share your conversations with advertisers, data brokers, or anyone else, for any purpose.

7. What is stored on your phone

All of it is inside the app's private storage, protected by iOS Data Protection and your device passcode. Deleting Undertone removes every item in this table from your phone.

8. Third parties

This is the complete list of companies involved in running Undertone:

RevenueCat identifies your subscription with an anonymous identifier it generates. We never send it your name, email, or any other personal detail, because we do not have one. Apple processes your payment; we never see your card details.

9. This website

The Undertone website sets no cookies, runs no analytics, and has no tracking pixels or advertising tags. The one external request each page makes is to Google Fonts to load its typefaces, which means Google receives your IP address and browser user-agent as part of serving that request. Our web host records standard server logs for security and reliability.

10. Notifications

Undertone may ask permission to send you local notifications — reminders generated on your own device. There are no push notifications, no remote message server, and no device token sent anywhere. You can turn notifications off in iOS Settings at any time.

11. Why we are allowed to do this (UK/EEA users)

If you are in the United Kingdom or the European Economic Area, our legal basis under the UK GDPR and GDPR is:

• Your consent (Art. 6(1)(a), and Art. 9(2)(a) for any special-category data a conversation may reveal) for analyzing a conversation. You give it on the consent screen, and you can withdraw it by simply not running further analyses.
• Contract (Art. 6(1)(b)) for providing and billing the subscription you bought.
• Legitimate interests (Art. 6(1)(f)) for keeping the service secure and working.

Because Undertone holds no account and stores nothing that identifies you, there is generally no stored personal data for us to retrieve, correct, or erase on request — but you retain your rights of access, rectification, erasure, restriction, portability, objection, and complaint. Write to furkankar6@icloud.com and we will help. You may also complain to your local supervisory authority.

12. US state privacy rights

If you live in California, Colorado, Connecticut, Virginia, or another state with a comprehensive privacy law, you have rights to know, access, correct, delete, and opt out of sale, sharing, and targeted advertising. To be explicit: we do not sell or share personal information, and we do not run targeted advertising, so there is nothing to opt out of. We will never discriminate against you for exercising a privacy right. Requests go to furkankar6@icloud.com.

13. International transfers

Fernix LLC is based in the United States, and our service providers process data in the United States and other countries. Where we transfer personal data out of the UK or EEA, we rely on the European Commission's Standard Contractual Clauses or another approved safeguard.

14. Children

Undertone is not directed to children. You must be at least 13 years old to use it, and if you are under the age of majority where you live, you may use it only with a parent or guardian's involvement. We do not knowingly collect personal information from children under 13. If you believe a child has used Undertone, contact furkankar6@icloud.com.

15. The other person in the chat

A conversation belongs to two people, and only one of them is holding the phone. Before you analyze a chat, make sure you have the right to share it, and consider what the other person would think. Undertone replaces names before sending, but the responsibility for what you upload is yours. Please do not analyze conversations obtained without permission.

16. Security

All traffic between the app and our service is encrypted with HTTPS, with no exceptions configured for insecure connections. Our API keys live in server-side environment variables and are never shipped inside the app. The strongest protection, though, is architectural: a service that stores no conversations cannot leak them.

No system is perfectly secure, and we do not claim otherwise.

17. Changes to this policy

If we change how Undertone handles data, we will update this page and move the "Last updated" date. For changes that meaningfully affect you, we will ask for your consent again inside the app rather than relying on you to re-read this page.

18. Contact

Fernix LLC
New Mexico, United States
furkankar6@icloud.com

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