Your data stays with you.
Grain is built for athletes who care about what their data says and where it goes. This policy explains, in plain English, what we collect, how we use it, and what we do not do with it.
What data we collect
- Health data — heart rate variability (HRV), resting heart rate, and sleep duration when you choose to connect Apple HealthKit.
- Training data — subjective wellness ratings, manual sleep entries, and other information you enter in the app to help calculate readiness.
- Usage data — app interactions needed to make the product work. We do not run third-party behavioural analytics inside the app.
- Account data — none. Grain currently does not require an account or login.
- Beta feedback / waitlist data — if you voluntarily submit your name and email through the website waitlist form, we collect that information so we can contact you about beta access.
How we use it
Health and training data are used solely to calculate your daily readiness score, recovery context, and training zone recommendation inside Grain.
Your health data is processed locally on your device. Grain is designed so that your HealthKit data does not leave your iPhone just to generate your score.
If you join the website waitlist, we use your submitted name and email only to contact you about beta access, updates, or launch information related to Grain.
What we do not do
- We do not sell your data.
- We do not share your health data with third parties.
- We do not use health data for advertising.
- We do not store your HealthKit data on our servers.
Your recovery data is for your training decisions, not for ad targeting, broker lists, or someone else’s analytics dashboard.
HealthKit
Grain only accesses Apple HealthKit data if you explicitly grant permission.
You can revoke that permission at any time through iOS Settings → Privacy & Security → Health.
We comply with Apple’s HealthKit rules. Health data accessed through HealthKit is not used for advertising, is not sold, and is not shared with data brokers.
Data retention
All health data used by Grain stays on your device.
If you delete the app, the locally stored app data is deleted with it unless your device or iCloud backups preserve a local backup copy under Apple’s normal backup behaviour.
If you submit your email to the waitlist, that information is stored securely through Formspree so we can manage beta access and communications.
Contact
If you have questions about privacy, email: grain-app@agentmail.to
Updates
We may update this policy as Grain evolves. If you continue using the app after a policy update is published, that means you accept the updated version.