Privacy Policy

Effective date: October 5, 2026 Last updated: October 1, 2026 Policy version: 2026-10-01

Washington, Nevada and Connecticut residents: additional disclosures about consumer health data are in our separate Consumer Health Data Privacy Policy.

1. Who we are and what this policy covers

Seylen ("Seylen," "we," "us," or "our") is an AI-powered emotional-wellness application for adults, operated by Harmonia LLC, a South Carolina limited liability company. This Privacy Policy explains what personal information we collect when you use the Seylen mobile app and related services (together, the "Service"), how we use and protect it, who we share it with, and the choices and rights you have.

Seylen is a non-clinical wellness product. It is a tool for reflection, emotional support, and general well-being for otherwise healthy adults navigating everyday stress. Seylen is not a healthcare provider. It is not a doctor, therapist, psychologist, psychiatrist, or other licensed medical provider, and it is not a substitute for professional medical advice, diagnosis, or treatment. Seylen does not diagnose, treat, cure, or prevent any medical or mental-health condition.

We are not a HIPAA covered entity. The Health Insurance Portability and Accountability Act (HIPAA) governs healthcare providers, health plans, and their business associates. Seylen is a direct-to-consumer wellness app and is none of these, so HIPAA does not legally apply to us. We describe elsewhere in this policy the security safeguards we voluntarily apply (see Section 6); where we mention HIPAA, we do so only as a benchmark for those safeguards and never as a claim of HIPAA status, compliance, certification, or responsibility for any of the same.

United States only. The Service is offered to, and intended only for, residents of the United States who are 18 years of age or older. It is not directed to, or intended for, people outside the United States (see Section 13).

If you do not agree with this policy, please do not use the Service.

2. Information we collect

We collect only the information we need to provide Seylen and to keep it safe. We do not buy personal information from data brokers, and we do not obtain it from clinical referrals or any third party — everything below comes either directly from you or is generated by Seylen from your own conversations with it.

2.1 Account information

Email address. Used to create and secure your account, sign you in, and send account-related messages (such as a password reset). For login we also store a one-way cryptographic hash of your email so we can look up your account without keeping your address in plain text.
Password. Stored only as a one-way, salted hash (bcrypt). We never store your actual password and cannot recover it.
Preferred name. The name you would like Seylen to call you.

2.2 Personalization you provide

During onboarding and in your settings you may choose to tell Seylen about yourself so it can support you in a way that fits you. This may include:

A short self-description (for example, descriptor chips you select about yourself).
Your communication-style preferences (for example, the tone you'd like Seylen to use).
Your care preferences (how you would like to be supported).

All of this is optional and self-provided. You can view and change it in the app.

2.3 Mood check-ins

If you use the mood check-in feature, we store the mood label you select. Moods are chosen by you from five simple, qualitative labels — lovely, good, okay, low, or heavy. These are your own self-reports. Seylen does not infer, score, or diagnose your mood from your conversations, and it does not attach any clinical interpretation to what you log. We keep your check-ins so you and Seylen can see how you've been over time.

2.4 Conversation content

When you chat with Seylen, we store the messages in the conversation — both what you write and what Seylen replies — so that your conversations have continuity and Seylen can remember what matters to you between sessions. Conversation content is the most sensitive information Seylen holds, and we treat it accordingly (see Sections 4 and 6).

2.5 Information Seylen derives from your conversations

To provide continuity, Seylen's own AI reads your conversations with it and generates a small amount of derived information about you, including:

Memories — short notes about facts or events you've mentioned.
Topics / themes — recurring subjects in your life that you return to, with an evolving summary of each.
A running profile summary — a narrative Seylen maintains to keep track of what it knows about you, which may include notes about people you mention and safety-relevant notes.
A short note of what you are currently carrying — a brief line about what is weighing on you at the moment, so a new worry is understood against everything else you are holding rather than in isolation. It fades on its own if you stop returning to it.
A tenderness marker on a memory. Seylen marks a memory as tender when it concerns something like grief, serious illness, a relationship rupture, or acute distress. The only thing this marker does is hold Seylen back: tender subjects are excluded from proactive check-ins, so Seylen never raises them first. It is not a diagnosis, a score, or an assessment of you, and it is not shown to you as a label.

This derived information is generated only from your own conversations with Seylen, by Seylen's self-hosted AI (see Section 4). It is not built from any outside source. You can view your memories and topics in the app and delete them individually (see Section 8).

2.6 Device and technical information

Push notification token. If you enable notifications, we store the push token your device provides (and your device platform and time zone) so we can deliver notifications you've asked for.
IP address. We record the IP address associated with certain security-relevant events (such as signing in or administrative actions) in a security audit log, to help us detect and investigate abuse. We do not use IP addresses to profile you or to serve advertising.
Safety markers. When Seylen's safety feature responds to a message with crisis resources (Section 12), we mark that message as having triggered it, and we set a quiet marker on your account. The quiet marker exists to make Seylen leave you alone: while it is set, Seylen will not send you proactive check-ins. It clears itself after a period of quiet. It is a yes/no marker, not a score, not a diagnosis, and not an assessment of your risk, and it is never shared outside Seylen.
A count of crisis referrals. We keep a running total of how many times the safety feature showed crisis resources, so we can publish that figure where the law requires it. This total is a number only — it is deliberately stored with no user identifier, no message, and no IP address attached, so it cannot be traced back to you or to anyone else.

2.7 Consent and compliance records

We keep a record of the privacy choices you make — for example, your confirmation that you are 18 or older, and your acknowledgment of how Seylen stores your conversations — together with the policy version in effect at the time. These records are legal evidence of consent (see Sections 7 and 9).

We also keep a record of the reports you choose to file about something Seylen said (Section 3), including the message you reported and any note you added.

2.8 Subscription and billing information

If you subscribe, we store your subscription status, which plan you chose, the amount and currency, your trial and renewal dates, whether a discount was applied, and identifiers issued by our payment processor that let us match your account to your subscription. We do not receive or store your card number, expiry, or security code — those go directly to the payment processor on a page it hosts (see Section 5).

2.9 Website visitors and the waitlist

If you ask us to tell you when Seylen launches, or otherwise sign up on our website, we store the name and email address you give us, together with the IP address and browser user-agent of that request, so we can contact you and so we can detect abuse of the form. We use these to send you the messages you asked for; you can unsubscribe from any of them at any time, and we keep a suppression record of that choice so we do not contact you again. A waitlist signup is not an account, and it does not create one.

3. How and why we use your information

We use the information described above only for the following purposes:

To provide and personalize the Service — to power your conversations with Seylen and to tailor its support to the preferences and personalization you've provided.
For memory and continuity — so Seylen can remember what matters to you and pick up where you left off, rather than starting over each time.
For safety — to detect language that may indicate a crisis and respond with fixed referrals to crisis resources such as the 988 Suicide & Crisis Lifeline (see Section 12). This detection is a simple keyword-based safety net, not a clinical risk assessment; it produces no risk score and no diagnosis.
For account security and integrity — to authenticate you, protect your account, enforce rate limits, maintain a security audit log, and detect and prevent fraud or abuse.
For notifications you've enabled — to send proactive check-ins and reminders you've opted into.
To take payment — to run your subscription, trial and renewals, and to send you the billing messages that go with them.
To handle reports about what Seylen says — you can report a reply that was offensive or wrong, directly in the app. When you do, we keep the reply you reported and anything you tell us about it, so that we can review it and correct how Seylen behaves.
To keep Seylen working properly — to check that what Seylen remembers about people is accurate and behaving as designed, to measure how the Service is performing in aggregate, and to fix it when it is not. This work is done on our own systems (Section 4). See "Our own access to your information" at the end of this section.
To communicate with you — for account and Service-related messages (such as password resets) and, unless you unsubscribe, the product emails described in Section 5.
To comply with law — to meet our legal obligations, to make the public disclosures some laws require of us, and to establish, exercise, or defend legal claims.

What we do NOT do. We do not use your information for advertising. We do not build advertising or marketing profiles about you. We do not sell your personal information, and we do not share it for cross-context behavioral advertising. See Section 4.

Our own access to your information

Nobody at Seylen sits in on your conversations, and no person reads along as you talk. Our own access is limited, purposeful, and recorded:

We can see your account details — such as your email address and subscription state — in order to run the Service and to answer you when you contact support.
We can see what you report to us. If you report something Seylen said, that reply and your note about it are kept where our team can review them. That is the point of the feature.
We check that Seylen's memory is behaving. Our own systems review a small, capped sample of recent activity each night to catch mistakes in what Seylen recorded — for example, treating something as finished when you never said it was. Where a problem is found, the finding may quote the exchange that caused it so we can understand and fix it. This runs entirely on our own infrastructure and is never sent to an outside AI provider (Section 4).
We can act on your account when we have to — for example, to fix a support problem you have asked us to fix, to test the Service, or to enforce these terms. Administrative access is restricted to authorized personnel, and administrative actions are written to an append-only audit log (Section 6).

We do not use your conversations to build or train a general-purpose AI model, and we do not use them for any purpose other than those described in this Section.

4. Our privacy promise: self-hosted AI, no trackers, no sale

These commitments are central to how Seylen is built, and we hold ourselves to them:

Your conversations are processed by Seylen's own self-hosted AI. The AI model that powers Seylen runs on our own infrastructure. Your conversations are never sent to any third-party AI provider — not to OpenAI, Anthropic, Google, or any other outside AI service — for the AI to generate its responses or to derive memories and topics. Your conversation content stays on Seylen's own systems for that processing.
No third-party analytics, advertising, or tracking SDKs. The Seylen app contains no third-party advertising, analytics, or tracking software development kits — no advertising pixels, no analytics trackers, no marketing profiling tools. We enforce this in our engineering process with an automated check that fails our build if a known tracker is ever added.
We do not sell your personal information, and we do not share it for advertising. There is no feature in Seylen that sells or shares your personal information for advertising or any similar purpose, and we do not ask you to consent to one because none exists. If we ever introduced any such sharing in the future, we would update this policy and obtain your consent before any sharing occurred.

5. Who we share information with (service providers)

We do not sell your personal information and we share it only with the limited set of service providers ("sub-processors") that help us operate the Service. Each sees only what it needs for its role. They act only on our instructions and may not use your information for their own purposes:

Category of provider	What it handles	Why
Network delivery and security	Encrypted network traffic in transit between your device and our servers, and your IP address at the network edge	To deliver the Service securely and protect it against attacks. Your connection is encrypted between your device and this provider, and again between the provider and our servers. As is standard for services of this kind, the provider terminates the encrypted connection at its own network edge in order to route and protect the traffic, so it is technically able to process it at that point. It acts only on our instructions and may not use your information for its own purposes.
Push notification delivery	Your device's push token, and the title and body text of the notifications we send you	To deliver the push notifications you have enabled. Notifications are then handed to your device's own platform push service (Apple's or Google's, depending on your phone). See the note below.
Email delivery	Your email address, and the content of the emails we send you — account emails (password reset, email-change confirmation, deletion notice), billing emails (receipts, trial reminders, failed payment, subscription changes), and, unless you unsubscribe, a short series of getting-started emails, occasional product announcements, and the odd note inviting you back	To deliver email. These emails do not contain your conversation content, memories, mood entries or topics — they carry only account, billing and product information. Email is not encrypted end-to-end in transit to your mailbox provider. You can turn any of the non-essential categories off (Section 8); we will still send the account and billing emails we are obliged to send.
Payment processing	Your email address, a customer identifier held by the processor, and your subscription status, plan and renewal dates. Card details go directly to the payment processor on a page it hosts — we never receive or store your full card number.	To take payment for paid plans and to run the billing portal where you update a card or cancel. The processor does not receive your conversations, memories, mood entries or any other wellbeing data.

The specific companies behind these categories. We maintain a current list of the named providers in each category and will provide it on request — write to [email protected]. We describe them by category here because that is what keeps this section accurate: a policy that names each vendor has to be republished every time infrastructure changes, and one that is not republished quietly stops being true.

A note about notification content. When we send you a proactive notification, its text is generated by Seylen's AI and may reference something from your own history — for example, "How did your meeting go?" Because a notification's text may include a brief reference like this, that text passes through our push-delivery provider, and then through your device's platform push service, in order to reach your device. We keep notification text brief for this reason.

Other than the categories of providers listed above, we do not share your personal information with anyone, except where required to do so by law or valid legal process, or as reasonably necessary to protect the rights, safety, or property of Seylen, our users, or the public.

6. How we protect your information

We apply administrative, physical, and technical safeguards designed to protect your information. Although we are not a HIPAA covered entity, we apply administrative, physical, and technical safeguards aligned with the HIPAA Security Rule's standards. Our specific controls include:

Encryption in transit. All traffic between the Seylen app and our servers is encrypted using industry-standard TLS (HTTPS/secure WebSockets), with modern cipher suites and HTTP Strict Transport Security. On iOS, Apple's App Transport Security is enforced so the app will not transmit over insecure connections.
Field-level encryption at rest for sensitive content. We encrypt your most sensitive information — including your conversation messages, the memories and topic summaries Seylen derives from them, your profile summary, care preferences, self-description, communication style, notes about people you mention, and safety notes, and your email address — at rest in our database, using strong symmetric encryption applied to those individual fields. Our production systems are configured to refuse to start if this encryption is not properly enabled, so that we do not run without it.
What is not yet field-encrypted. To be transparent: some lower-sensitivity or health-adjacent fields are not yet covered by this field-level encryption at rest — specifically your mood-check-in labels, topic labels (as distinct from the encrypted topic summaries), your preferred name, IP addresses in the security audit log, push tokens, the safety markers described in Section 2.6, your subscription and billing record, and the name, email and technical details captured by a waitlist signup. These remain protected by encryption in transit, by access controls, and by the security of our infrastructure, and we are working to extend field-level encryption to cover them. We therefore say that your sensitive conversation and profile data is encrypted at rest — we do not claim that all data is field-encrypted at rest.

Access controls and auditing. Access to the Service is protected by authentication (bcrypt password hashing; short-lived session tokens with rotation; rate limiting on sensitive endpoints). Administrative access is restricted, and security-relevant events are recorded in an append-only audit log.
Session protections. Idle chat sessions time out automatically, and the app offers a biometric (Face ID / fingerprint) lock so your conversations stay protected on your device.

No method of transmission or storage is perfectly secure, and we cannot guarantee absolute security. We encourage you to use a strong, unique password and to keep your device secured.

7. How long we keep your information

We retain your information for as long as you keep your account, so that Seylen can continue to support you with continuity over time. We keep your data until you delete it or close your account (see Section 8) — we do not apply a fixed retention period or an automatic deletion schedule to your conversations, your mood check-ins, or your memories, apart from the temporary notes described next.

Some memories are temporary. Notes about upcoming plans, like an appointment or a trip, are cleared automatically a few weeks after they're over. Anything lasting stays in your profile until you delete it.

When you delete your account, we delete the associated data as described in Section 8. A small number of records survive, each stripped of the link to you:

the limited consent and compliance records described in Section 2.7, and a security-audit record with your account identifier and the IP address it was recorded from removed, because we are required to keep evidence of the privacy choices you made;
a record that an email was sent to you, with your address replaced by a random code that no one can turn back into your address, and the link to your account removed, so we can prove what we sent;
the aggregate crisis-referral count described in Section 2.6, which is a number with nothing attached to it.

Four further points, so that nothing here is a surprise:

Backups keep a copy for a short time after you delete. We take a routine backup of our database once a day and keep each one for 14 days before it is overwritten. Data you delete is removed from the live service on the schedule in Section 8, but a copy can remain in an unexpired backup for up to 14 days after that. Backups are held on storage we control and are never used to restore an individual record; the sensitive fields inside them remain encrypted, exactly as they are in the live database.
A report you file about something Seylen said survives you deleting that conversation. It is kept as the record of a complaint, and it is deleted when you delete your account.
Our payment processor keeps its own record of the payments it processed for us, under its own policy and for as long as tax and accounting law requires. Deleting your Seylen account cancels any live subscription and removes our copy; it does not erase the processor's transaction records.
A waitlist signup is not tied to an account, so deleting an account does not remove it. Ask us and we will delete it, or unsubscribe and we will stop contacting you.

8. Your rights and choices

We've built Seylen so you can see and control what it knows about you. Below is an honest description of what you can do today. Where a capability is partial or not yet built, we say so.

Delete your account and data (available). You can permanently delete your account from within the app. Deletion is scheduled rather than instant: your account is closed straight away and is permanently erased 24 hours later. The delay exists so that a deletion made in a bad moment, or by someone else on your phone, can be undone — you can cancel it from the app at any point inside that window, and nothing has been erased yet. Once the window passes the erasure runs, and we cannot retrieve your data for you afterwards; as described in Section 7, a copy can remain in an unexpired backup for up to 14 days. Deletion removes your conversations, messages, memories, topics, mood check-ins, profile and personalization, notification settings, push tokens, subscription record, and session credentials, and it cancels any live subscription so you are not billed again. (As described in Section 7, a few de-identified records survive.)
Delete individual items (available). You can delete individual memories and individual topics that Seylen has stored, without deleting your whole account. You can also set a topic aside so Seylen stops returning to it, and bring it back later.
View what Seylen remembers (partial). You can view the memories and topics Seylen has stored about you, and you can view and edit your personalization. We do not offer a full, machine-readable export or download of all your data. If you have questions about your information, contact us (Section 15).
Correct your information (partial). You can edit your personalization at any time, and you can delete individual memories that are wrong. We do not yet offer a general tool to correct a specific AI-derived inference other than by deleting it. If something Seylen has recorded about you is inaccurate, you can delete it or contact us.
Withdraw consent (partial). Because storing your conversations is essential to how Seylen works, the app does not currently offer a way to withdraw consent to that storage while keeping your account. If you no longer wish us to store your conversations, you can delete your account, which removes them.
Manage notifications. You can turn notifications on or off, and adjust quiet hours and related preferences, in the app and in your device settings.
Manage email. Every non-essential email we send carries an unsubscribe link, which also lets you turn off individual categories rather than all of them. Unsubscribing does not stop the account and billing emails we are obliged to send — password resets, security notices, receipts and the like.
Report something Seylen said. You can report any reply, from inside the app, without leaving it. We read what you send (see "Our own access to your information" in Section 3).

We will not discriminate against you for exercising any privacy right.

9. Consent

Before you begin using Seylen, we ask you to agree — explicitly, by ticking a box — to three separate things, on three separate screens:

Storing your conversations. "I agree to let Seylen store my conversations so it can support me over time."
That you are an adult. "I confirm that I am 18 years of age or older."
These policies. "I agree to the Terms of Service and Privacy Policy."

Each is its own act, and none of them is bundled with another. You cannot move past a screen without the tick that belongs to it. We record each consent separately, with the policy version in effect and a timestamp, in an append-only record (see Section 2.7).

We do not sell or share your information for advertising, so we do not ask for — and you are never asked to give — consent to any such sharing.

We do not sell or share your information for advertising, so we do not ask for — and you are never asked to give — consent to any such sharing.

10. Children's privacy

Seylen is intended only for adults 18 years of age or older. The Service is not directed to children, and we do not knowingly collect personal information from anyone under 18. During onboarding, we tell you that Seylen is for adults only and ask you to confirm that you are at least 18; we record that confirmation. We rely on your attestation — we do not collect a date of birth or otherwise verify age. If you believe someone under 18 has provided us with personal information, please contact us (Section 15) and we will delete it.

11. Your U.S. state privacy rights

Depending on where you live, you may have additional rights under your state's privacy laws. We honor these rights for the personal information described in this policy.

California (CCPA/CPRA)

If you are a California resident, you have the right to know what personal information we collect and how we use it (described throughout this policy), the right to request deletion of your personal information, and the right to correct inaccurate personal information — which you can exercise using the tools described in Section 8 or by contacting us (Section 15). California also gives you the right to opt out of the "sale" or "sharing" of your personal information and to limit the use of sensitive personal information. We do not sell your personal information and we do not share it for cross-context behavioral advertising, so there is nothing to opt out of. We will not discriminate against you for exercising your rights. We do not currently offer a Global Privacy Control opt-out signal mechanism because we do not sell or share personal information.

Washington

If you are a Washington resident, additional disclosures about how we handle consumer health data apply to you, and are provided in our separate Consumer Health Data Privacy Policy. That policy addresses the specific rights and protections the Washington My Health My Data Act provides, including consent, access, deletion, and the right not to have consumer health data sold (we do not sell it).

Other states

Residents of other states with comprehensive or consumer-health privacy laws — including, for example, Nevada, Connecticut, Colorado, Virginia, Oregon, Texas, Maryland, Minnesota, and others — may have rights to access, delete, or correct their personal information, and to opt out of targeted advertising, sale, and certain profiling. Because we do not sell personal information, do not share it for targeted advertising, and do not profile you for those purposes, several of these rights are not implicated by how Seylen works. To exercise any right you believe you have, contact us at the address in Section 15, and we will respond as required by applicable law.

12. Crisis and non-clinical notice

Seylen is not a medical, emergency, or crisis service. It is not designed for emergencies, crisis intervention, or urgent mental-health support, and it cannot assess or manage a crisis.

If you are in crisis or think you may be having a medical or mental-health emergency, do not use Seylen to get help. Instead:

Call or text 988 to reach the 988 Suicide & Crisis Lifeline, or
Text HOME to 741741 to reach the Crisis Text Line, or
Call 911 or go to your nearest emergency room.

Seylen includes a safety feature that watches for crisis language and responds with these referral resources, but that feature is a simple safety net, not a substitute for professional or emergency help. If the same conversation returns to it, Seylen offers a wider set of routes — including a chat option and a national helpline that can point you toward ongoing care — rather than repeating itself. Seylen also stops and offers these resources if you describe wanting to seriously harm someone else. Seylen does not contact anyone on your behalf — not emergency services, not a family member, not anyone. A fuller description of what this feature looks for and what it does not do is published at seylenapp.com/crisis-protocol.

13. International users

The Service is intended only for residents of the United States. It is not directed to individuals in the European Union, the European Economic Area, the United Kingdom, or other jurisdictions outside the United States, and we do not offer it to them. If you access the Service from outside the United States, you do so on your own initiative, and your information will be processed in the United States.

14. Changes to this policy

We may update this Privacy Policy from time to time. When we do, we will revise the "Last updated" date above and update the policy version. If we make material changes, we will provide notice through the app or by other reasonable means before the changes take effect, and, where required by law, we will obtain your consent. Your continued use of the Service after an update takes effect means you accept the updated policy.

15. How to contact us

If you have questions about this policy or your privacy, or if you'd like to exercise a privacy right, contact us at:

Email: [email protected]
Operated by: Harmonia LLC, 6650 Rivers Ave, STE 100, Charleston, SC 29406, United States

This policy is published at https://seylenapp.com/privacy, which is the same URL used in the App Store, on Google Play, in the app, and on our website.

This policy is published at https://seylenapp.com/privacy.