Privacy Policy

Last updated: 29 October 2026

Who we are

Tethril is an AI life manager at tethril.com. For data-protection purposes the controller is:

• Entity: [legal entity: not yet stated]
• Address: [registered address: not yet stated]
• Privacy contact: privacy@tethril.com

We are small enough that we are not required to appoint a Data Protection Officer, so privacy requests go to the address above and are handled by a person, not a queue.

What we collect

• Account data: email, display name and avatar, held by our authentication provider (Clerk). We store the user ID it issues.
• Product data: the events, tasks, notes, habits, goals and settings you create, and your conversations with the AI assistant. Photos you add to a note are stored with it.
• Phone calendars (iPhone and iPad app, only if you turn them on): the title, time and location of events in the calendars you choose, read-only. They are copied to our servers so your schedule and Reeve can see them. Reeve is told only when you are busy, never an event's title.
• Widgets: so a Home Screen widget can tick a task while the app is closed, the app gives the widget a random device token. We store only a hash of it, tied to your account, and it stops working after 90 days unused or when you sign out.
• Setup counters: which setup steps you reached and whether you agreed to Reeve, kept as counts on your account in our own database. They hold no content and no third party sees them.
• Operational data: server request logs and error reports. User IDs in logs are hashed with a per-environment salt so they cannot be correlated between environments.
• Feedback: if you use Send feedback, we receive your message, the email on the form (filled in from your account, and you can change or clear it), the page you were on, your window size and your browser or device version. We link it to your account while it exists. Deleting your account erases the email and the page, window and device details from your feedback and unlinks it from you. The message text stays, so write nothing in it you would not want kept; ask at the privacy address above to have it removed too.
• Analytics: aggregate page views and performance timings. See Analytics; this does not use cookies and does not follow you between sites.

We do not ask for, and have no use for, special-category data: health, biometrics, political or religious views. Please don't put it in a note.

Why we're allowed to (lawful bases)

• Performance of a contract: running the product, storing your plan, sending transactional email.
• Legitimate interests: keeping the service secure, debugging errors, and measuring aggregate usage so we know which parts to improve. We've weighed these against your interests; each is low-impact and none involves profiling or advertising.
• Consent: only where we ask for it explicitly, such as optional product emails. You can withdraw it at any time.

What we never do

• We do not sell personal data, and we have not in the preceding 12 months.
• We do not share it with advertisers, data brokers or ad networks.
• We do not use your content to train AI models of our own. What Google does with data sent to the Gemini API is set by Google's own terms for that API.
• We set no advertising or cross-site tracking cookies.

Sub-processors

These are the third parties that process personal data on our behalf, each under a data-processing agreement. "Active" means it is running in production today; "conditional" means the integration ships in the code but stays dormant until credentials are set, and processes nothing until then.

We'll update this table before adding a processor, not after. If you want to be told when it changes, email privacy@tethril.com and we'll add you to the notice list.

Analytics

We use Vercel Web Analytics and Vercel Speed Insights to count page views and measure load performance. Both are privacy-preserving by design: they set no cookies, read nothing from your device, and build no cross-site profile. Vercel derives a rotating, non-reversible visitor hash rather than storing an identifier, so we cannot single you out or follow you to another site.

Because it touches your IP address in transit, it is still processing personal data, which is why it's disclosed here. Our lawful basis is legitimate interests. It's also why we don't show a cookie banner. See the Cookie Notice for the reasoning.

The AI assistant

Reeve is powered by Google's Gemini API, and it only runs after you have agreed to that. The first time you set up Tethril, or the first time you use Reeve if you skipped it, we ask. You can turn Reeve off at any time in Settings → Reeve, and it stops at once.

When you ask the assistant to plan something, we send Google your message and the recent conversation, your name, time zone and working hours, today's events, your open tasks and habits, and the things Reeve remembers about you. If Reeve needs more, such as your notes or another week, it looks them up and sends only those. Calendar events from your phone or an imported calendar are sent as busy time only, without their titles.

When you speak to Reeve, your phone turns your voice into text with Apple's speech recognition, which may use Apple's servers. Only the text reaches us and Google; we do not receive or keep your audio. If we turn on the ElevenLabs voice (not available yet), your voice audio during that call goes to ElevenLabs instead.

Small changes Reeve makes are applied at once, and each one comes with an Undo. A big change, such as planning a whole day, waits for you to choose "Do it" or "Cancel" first.

International transfers

We're hosted in the United States, so if you're in the UK, EEA or Switzerland your data is transferred there. Those transfers rely on the European Commission's Standard Contractual Clauses (with the UK Addendum where relevant), incorporated into our agreement with each provider above.

How long we keep it

• Your content: until you delete it, or until you delete your account.
• Deleted accounts: a 7-day grace period in case you change your mind, then permanent erasure from live systems. Encrypted backups age out within 30 days.
• Server logs: 30 days.

Security

Data is encrypted in transit (TLS) and at rest. Access to production is limited to those who need it. No system is perfect, and we won't pretend otherwise. If a breach affects you, we'll notify you and the relevant regulator within 72 hours of becoming aware of it, as the law requires.

Your rights

Wherever you live, you can export everything and delete your account yourself, without asking us, from Settings → Privacy and data. The export is a single JSON file containing every event, task, note and setting.

If you're in the UK or EEA, the GDPR also gives you the right to:

• access, correct or erase your data;
• restrict or object to processing, including anything based on legitimate interests;
• receive it in a portable format (that's the export);
• withdraw consent where we relied on it; and
• complain to your data protection authority (in the UK the ICO). We'd appreciate the chance to fix it first.

If you're in California, the CCPA/CPRA gives you rights to know, delete, correct and opt out of "sale" or "sharing". We don't sell or share personal data as those terms are defined, so there is no opt-out to offer, and we will not discriminate against you for exercising any right.

For anything the in-app tools don't cover, email privacy@tethril.com. We'll respond within 30 days and won't charge you for it. We may need to confirm you control the account's email address first.

Children

Tethril isn't for children. You must be at least 16 to use it (13 in the US, with the age of digital consent in your country taking precedence where it is higher). We don't knowingly collect data from children; if we learn we have, we'll delete it.

Changes

We'll post any change here and move the date at the top. If a change materially affects your rights, we'll email you before it takes effect.

Contact

Privacy questions: privacy@tethril.com. Everything else: support@tethril.com.