Privacy Policy

Last updated: 27 October 2026

Who we are

Halcyo is provided by HESTERVALE LLC, 30 N Gould St Ste N, Sheridan, WY 82801, USA (“we”, “us”). We are the controller for the processing described here. You can reach us at privacy@halcyo.app.

Privacy Officer: Privacy Officer, HESTERVALE LLC, privacy@halcyo.app. This is the person in charge of the protection of personal information for Canada and Quebec, and our data protection officer (encarregado) under Brazil’s LGPD.

Data that stays on your phone

The app stores the following only on your device. In the current version, none of it is sent to us or to anyone else.

• Your answers to the opening questions, including information about your tinnitus and how it affects you
• Your matched tone, sound settings and sleep timer
• Daily check-ins (loudness, distress, stress, sleep and the factors you tick)
• Lesson progress, reminder time and language
• On Android, the country of your Google Play account, which the app reads through RevenueCat to show the right emergency and crisis numbers

Your answers and check-ins describe your tinnitus and how it affects you, so they are health information. We don’t sell it, don’t use it for advertising and don’t share it. If you live in Washington State or another US state with a consumer health data law, see our Consumer Health Data Privacy Policy.

You can share a copy of this data from Settings → Your data → Share my data, and delete it from Settings → Your data → Delete all my data. Deleting the app also deletes it.

Coach messages (not available yet)

The coach is not available in the current version of Halcyo, and the app sends no coach data. This section describes how it will work and applies only once we turn it on; we will update the date of this policy and tell you in the app first. Once available, the coach is optional and keeps its conversation history on your phone. When you send a message, the app sends the following to our coach server, which runs on Cloudflare:

• the text of your recent conversation (up to the last 8 messages that fit in 8,000 characters)
• your app language
• your matched tone, your impact level from the opening questions and your program day, so replies fit your plan
• an anonymous app user ID, used to check your subscription and the daily message limit

Our server forwards the conversation to Anthropic PBC, which provides the Claude AI model that writes the reply, and returns the reply to your phone. We don't store message content on our server and don't use it to train AI models. Anthropic processes it as our service provider under its commercial terms, does not use it to train its models, and may keep it for a limited period for safety and abuse monitoring, as described in Anthropic’s privacy policy.

Because these messages can contain health information, we process them only on the basis of your explicit consent (Art. 9(2)(a) GDPR). Before your first message, the coach shows what is sent and to whom, and nothing is sent until you tap I agree; our server refuses messages without that consent. You can withdraw it at any time in Settings → Coach → Withdraw coach consent, which also deletes the conversation stored on your phone. Withdrawing doesn't affect replies you already received. Please don’t include your name or other details that identify you.

Subscriptions

Purchases are made through the App Store or Google Play. We never see your name or payment details. To check whether your subscription is active, the app uses RevenueCat, Inc., which receives an anonymous app user ID, purchase receipts, and basic device and app information. Legal basis: performance of our contract with you (Art. 6(1)(b) GDPR).

What our server keeps

Our server exists for the coach. While the coach is not available, the app sends nothing to it. Once the coach is available, the server keeps:

• A count of coach messages per anonymous user ID for the current day, deleted 48 hours after that day ends
• An active subscription status, cached for 10 minutes
• Standard request logs kept by Cloudflare for security, such as IP address and time, under Cloudflare’s retention rules

Cloudflare also hosts this website and keeps the same kind of request logs for visits to it.

Legal basis: our legitimate interest in running the service securely and preventing abuse (Art. 6(1)(f) GDPR).

Notifications

The daily check-in reminder is scheduled on your phone. There is no push server.

No advertising or tracking

Halcyo contains no advertising and no analytics or tracking tools, and we don’t sell or share personal data for advertising. If we ever add crash reporting or usage analytics, we will update this policy first and describe exactly what is collected.

Service providers and transfers

We use RevenueCat, Inc. (subscription status) and Cloudflare, Inc. (hosting of this website). Once the coach is available, Cloudflare also hosts the coach server and Anthropic PBC writes the AI replies. They are based in the United States. Where data leaves the European Economic Area, the UK or Switzerland, transfers rely on the EU–US Data Privacy Framework where the provider is certified, or on Standard Contractual Clauses.

Your rights

Depending on where you live, you have the right to access, correct, delete or export your personal data, to restrict or object to processing, and to withdraw consent at any time. Most of your data is only on your phone, so you can see and delete it yourself in the app: Settings → Your data → Delete all my data. For anything else, including deleting your purchase record held by RevenueCat, email privacy@halcyo.app. We answer within the time the law where you live requires. You can also complain to your local data protection authority.

Children

Halcyo is for people aged 16 and over. It is not intended for children under 16, and we don’t knowingly process their data. Its App Store age rating is 16+.

Changes

We will post any changes on this page and update the date at the top. If a change is significant, we will also tell you in the app.

Contact

privacy@halcyo.app