Last updated: 9 June 2026

Privacy Policy

Isochron is built to be private by default. Your watch collection lives on your device, the microphone and camera are used only to measure your watches, and we collect as little as possible — and only what you choose to share.

This policy explains what Isochron ("we", "us", or "the app", operated by the Isochron team) collects, how it's used, and the choices you have. It covers both the iOS app and the website at isochron.watch.

Data stored on your device

Your collection — the watches you add, their photos and specifications, your accuracy measurements, service records, and warranty details — is stored locally on your device. If you enable iCloud on your device, this data is synced and backed up through your own private iCloud account using Apple's CloudKit. In that case Apple processes it under Apple's Privacy Policy; we do not have access to your iCloud-synced collection.

Microphone and camera

• Microphone is used to listen to your watch's ticks so the app can measure its rate and beat error. This audio is processed on your device in real time and is not recorded, stored, or sent to our servers.
• Camera and photos are used so you can photograph a watch face (to measure worn accuracy) and add photos to your collection. These images are stored on your device (and in your iCloud if enabled). We do not upload your photos to our servers.

Information you choose to share with the community

Isochron includes optional community features. These are off until you use them:

• Accuracy contributions. If you contribute a reading to the community, we receive the measurement itself — such as the rate (seconds per day), beat error, beat rate, resting position, confidence, and the watch model or movement it applies to. We do not receive your name, photos, or location with it. Contributions are associated with your account identifier so we can prevent abuse and filter outliers.
• Forum. Threads and replies you post are stored on our servers and shown publicly to other users, attributed to the display name you choose.

Accounts and Sign in with Apple

By default your community identity is anonymous: the app registers a random device token, and we store only a hashed version of it. No name or email is required to use the app or contribute.

If you choose Sign in with Apple, we receive a stable, Apple-provided identifier for your account (not your real Apple ID) so your account works across devices. We only receive your name or email if you explicitly provide a display name. We verify Apple identity tokens against Apple's public keys and never see your Apple password.

The website and waitlist

If you submit your email address to the launch waitlist on isochron.watch, we use it solely to notify you about availability and then stop. The website does not use third-party advertising or tracking cookies.

What we do not do

• We do not sell or rent your personal information.
• We do not show ads.
• We do not use third-party advertising networks or cross-app tracking.

Who we share data with

We share data only with the infrastructure providers needed to run the service — for example our server hosting and database. We use Apple for CloudKit sync and Sign in with Apple. We may disclose information if required by law.

Security

Traffic between the app and our servers is encrypted with HTTPS. Account tokens are stored only as cryptographic hashes. No method of transmission or storage is perfectly secure, but we take reasonable measures to protect your data.

Retention and your choices

• Deleting the app removes the collection stored on your device. iCloud-synced data is managed in your iCloud settings.
• You can ask us to delete your community account and contributions at any time by emailing us.
• Where applicable law gives you rights — such as the GDPR or CCPA — you may request access to, correction of, or deletion of the data we hold about you, and you may object to or restrict certain processing. Contact us to exercise these rights.

Children

Isochron is not directed to children under 13, and we do not knowingly collect personal information from them.

Changes to this policy

We may update this policy from time to time. We'll revise the "last updated" date above and, for material changes, provide notice in the app or on the website.

Contact

Questions or requests about privacy: privacy@isochron.watch.

This policy reflects how the app is built today. If you operate Isochron through a registered legal entity, add its name and address here, and have the text reviewed for the jurisdictions you serve (e.g. EU/UK GDPR, California CCPA/CPRA).