Last updated: September 22, 2026

Lintra looks for a connection between your heart-rate variability and what repeats on your calendar. Because that means reading data from Apple Health and, optionally, Calendar, this policy is specific about exactly what is read, where it goes, and where it stays.

Short version

• Lintra reads one type of Health data: heart-rate variability (HRV) samples. It does not read resting heart rate, sleep, or anything else from Health.
• Calendar access is optional and, if granted, Lintra reads only event titles and times — never notes, attendees, or locations.
• Your baseline, the dip detection, and the sentence describing a pattern are all computed on your device.
• There is no account and no server that holds your health or calendar data. Nothing is transmitted.

No account, no identity

Lintra has nothing to sign in to. We do not ask for a name, an email address, a phone number, or a social login, and we do not create an identifier that follows you across apps or devices. We have no means of knowing who you are, and no record of you to look up if asked.

What Lintra reads from Health

Lintra requests permission to read heart-rate variability (HRV) samples from Apple Health — specifically the SDNN measurement your Apple Watch already records. That is the only Health data type Lintra asks for. It does not request, and cannot read, resting heart rate, sleep data, or any other Health record. You can review or revoke this at any time in iOS Settings → Privacy & Security → Health → Lintra.

Lintra also declares the ability to write to Health, but it never does — it requests no permission to add or change anything in Health, and no code path in the app writes a record.

What Lintra reads from Calendar

Calendar access is optional. If you grant it, Lintra reads the titles and times of events already on your calendar, so it can check whether a recurring event lines up with an HRV dip. Lintra never reads event notes, attendees, or locations, and it never creates, edits, or deletes a calendar event. If you decline or later revoke access in iOS Settings → Privacy & Security → Calendars, Lintra keeps working — it simply cannot name a stress-cause candidate, since that requires comparing HRV dips against your calendar.

Where the analysis happens

Everything Lintra does with your HRV and calendar data — computing your 28-day baseline, detecting a dip below it, matching dips against recurring events, and writing the sentence that names a candidate — runs entirely on your device. None of it is sent to a server, none of it is processed by a third-party AI service, and Lintra operates no backend that could receive it even if it wanted to.

What is stored, and where

Lintra stores its data in the app’s own container on your device: your computed baseline, the dips it detected, the calendar titles it matched against them, and any stress-cause candidates it named. None of it is copied anywhere else. You can delete all of it at any time from Settings → Delete My Data inside the app, and deleting the app removes its container, and everything in it, from your device.

The subscription

Lintra is a subscription, purchased and billed through the App Store. We never see or handle your payment details; Apple processes the payment.

To know whether a subscription is active on this device, Lintra uses RevenueCat, a subscription-management service, as its processor. RevenueCat receives an anonymous, randomly generated identifier for the install and the App Store subscription record for this app — which plan was purchased, its status, and renewal information. It receives none of your HRV samples, none of your calendar data, and nothing about the stress-cause candidates Lintra names. We use it only to unlock what you subscribed to.

This is the only reason Lintra makes a network request at all. If the device is offline, the baseline calculation and stress-cause matching still run as normal on data already on the device.

No advertising, no analytics, no tracking

Lintra contains no advertising SDK, no analytics SDK, and no attribution or crash-reporting service that would leave the device. It does not use the Advertising Identifier and does not ask for tracking permission, because it has nothing to track you with.

Children

Lintra is intended for adults and is not directed to children. We do not knowingly collect personal data from children, and since there is no account and no server, we hold no personal data from any user, of any age.

Not a medical device

Lintra reads HRV samples and compares them against your calendar. It does not diagnose, treat, or prevent any condition. What it shows is a correlation it observed between two records it read — never a cause asserted as fact. Nobody should use Lintra to make a medical decision. See our Terms of Use for the limits of what it can tell you.

Changes to this policy

If we change how Lintra handles data, we will update this page and the date at the top. Because the app holds no contact details for you, this page is where changes are published.

Contact

Questions about this policy, or about the app, go to ootssu@ootssu.com.