Privacy Policy

Last updated 11 October 2026

The short version

Your habits live on your phone first. We keep a copy in your account so you don’t lose them and can use more than one device.
We don’t sell your data, show ads, or track you across other apps and websites.
A few trusted services help us run Keyston. They only get what they need to do their job.
You can download your data or delete your account, in the app, at any time.

Who we are

Keyston is a habit app made by Keyston (“we”). If you have a question about your data, email support@keyston.app.

What we collect, and why

Your account

Your email address, so you can sign in and we can send sign-in codes. If you use Sign in with Apple, Apple gives us an ID and an email address (which can be a private relay address if you choose “Hide My Email”), and your name if you share it.

What you write in the app

Your habits and everything about them (names, plans, reasons, promises, notes), your check-ins, pauses, journal lines and settings. This is stored on your device and, once you have an account, copied to our servers so it is backed up and appears on your other devices.

Notifications

If you turn on reminders or nudges, we store a notification token for your device so we can send them. Alarms and local reminders are scheduled on your phone.

Purchases and stakes

If you subscribe to Keyston Plus, Apple handles the payment; we learn from Apple (through RevenueCat) whether your subscription is active. If you put money on a habit (stakes), Stripe stores your card. We never see or store your full card number; we keep the card brand, the last four digits, and a record of each charge.

Feedback

If you send feedback, we receive your message and anything you choose to attach, such as a screenshot or your email address.

Technical data

Like any server, ours briefly logs basic request details (such as IP address and time) to keep the service secure and working. We don’t use these logs to profile you.

AI features

Two features use an AI model provided by Anthropic:

Writing help: when you create a habit, the text you type may be sent to fix grammar and wording.
Mentor chat: the messages you send, plus a short summary of your habits, streaks, misses and promises so the mentor can answer you, are sent to Anthropic to write a reply. Your chat history is stored with your account so you can see it later.

Anthropic processes this data to provide the service to us and does not use it to train its models under our agreement. Don’t share anything in the chat you wouldn’t want processed this way. The mentor is not a therapist or a medical service.

Services we use

Vercel runs our servers and API.
Neon hosts our database.
Resend sends sign-in codes by email.
Apple provides Sign in with Apple, notifications and in-app purchases.
RevenueCat keeps track of Keyston Plus subscriptions.
Stripe stores cards and processes charges for stakes.
Anthropic provides the AI model for writing help and the mentor chat.

Some of these services are in the United States. Where the law requires it, we rely on standard contractual safeguards for these transfers.

What we don’t do

No advertising, no ad networks, no selling or renting your data.
No tracking across other companies’ apps or websites, and no third-party analytics SDKs.
Habit names are left off your lock screen unless you turn them on.

How long we keep it

We keep your data while you have an account. When you delete your account, we delete it from our servers straight away, and from backups within 30 days. Stripe and Apple keep their own payment records as the law requires.

Your choices and rights

Download your data from You › Data in the app.
Delete your account from You › Account in the app. This removes your account and everything in it from our servers and from your phone, stops any stakes, and cancels your alarms and reminders. An App Store subscription is managed by Apple: cancel it in your iPhone’s Settings.
Depending on where you live, you may also have the right to access, correct or move your data, or to object to how we use it. Email us and we’ll help within 30 days. You can also complain to your local data protection authority.

Children

Keyston is not meant for children under 13, and stakes are only for adults (18+). We don’t knowingly collect data from children.

Security

Data travels over encrypted connections, sensitive fields are encrypted at rest, and access to production systems is limited. No system is perfect; if something goes wrong that affects you, we’ll tell you.

Changes

If we change this policy in a way that matters, we’ll tell you in the app before it takes effect.