Pillar

Privacy Policy

Effective date: September 7, 2026 · Last updated: September 7, 2026

The short version. Pillar reads head position from your AirPods and analyses it on your iPhone. Raw motion data never leaves your device, there is no account, and there is no camera or photo of you anywhere in the product. We do send a small set of anonymous product analytics — session scores, which permissions were granted, and your calibration angles rounded to the nearest 5° — and Apple handles every payment. We never sell or share personal data.

This policy explains what Pillar (“Pillar”, “we”, “us”) does with data when you use the Pillar iPhone app. Pillar is developed and operated by Maksym Pustovit. You can reach us any time at glowdapp@gmail.com.

1. What we do not collect

2. On-device processing

When you wear AirPods with motion sensors and start a session, Pillar receives head-orientation readings from iOS several times a second. All of the following happens locally on your iPhone:

None of the underlying readings are uploaded. What leaves the device is only the summarised, anonymous analytics described in section 4.

3. What is stored on your device

You can erase all of it from inside the app: You → Delete my data. Deleting the app removes it as well.

4. Analytics

We use PostHog to understand how the app is actually used, so we can fix what is broken and drop what nobody needs. Events are tied to a random identifier generated on your device, not to your identity. This is the complete list of what we send:

EventWhat it carries
App opened / became active / backgroundedNothing beyond the timestamp and the device properties below.
Session startedOpen-ended or Pomodoro, planned number of cycles, whether motion permission is granted.
Session endedDuration in minutes, score, share of time in poor posture, number of nudges and how many you heeded, longest tall stretch, which session number it was for you, how the session was ended.
Session blockedThe reason a session could not start (for example, AirPods not connected).
Permission resultWhether Motion & Fitness and notifications were granted or denied.
Calibration completedYour tall angle, slouched angle and the spread between them, each rounded to the nearest 5° — never the exact measurement.
Streak milestoneThe number of days reached.
Setting changedWhich setting, and its new value.
Device properties, attached to all of the aboveDevice model, iOS version, app version, locale and time zone, an anonymous app-install identifier, and your IP address — which PostHog uses to derive an approximate region and does not expose to us as a precise location.

This website

The pages on pillar.glowd.tech send the same PostHog project three events, and nothing else: site_page_viewed (which page, and the domain you arrived from — not the full referring address), site_cta_clicked (which App Store button you pressed and where on the page it sat) and site_faq_opened (which question you expanded). Your IP address reaches PostHog with them, as it does with any web request.

The site sets no cookies and writes nothing to your browser's storage: web analytics here is kept in memory for the length of the page visit and then discarded, so you are not recognised on a later visit or followed to another site. That is also why there is no cookie banner to dismiss. If your browser sends a Do Not Track signal, nothing is sent at all. Session and screen recording are switched off.

We deliberately report body angles only in 5° buckets. Precise measurements of somebody's neck are the kind of data that should not be collected without a reason, and the questions we need answered do not require them.

PostHog's own privacy policy is at posthog.com/privacy.

5. Purchases and subscriptions

If you subscribe, the payment is processed entirely by Apple through the App Store. We never receive or store your card number, billing address or Apple Account credentials.

We use RevenueCat to check whether a subscription is active. RevenueCat receives a randomly generated app user ID, your purchase receipts from Apple and your subscription status. It receives no payment card details and no posture data. Its privacy policy is at revenuecat.com/privacy.

6. Notifications

If you allow notifications, Pillar can post a nudge as a local notification when it cannot reach you any other way. These are composed and scheduled on your device — there is no push server, and no device token is sent to us. You can revoke the permission at any time in Settings → Pillar → Notifications.

7. Third parties we rely on

ServicePurposeWhat it receives
Apple (App Store, iOS)Distribution, payments, motion sensor access, notificationsApple handles all payment data. Head-orientation readings are provided by iOS to the app on your device.
PostHogAnonymous product and website analyticsSee section 4.
RevenueCatSubscription statusSee section 5.

None of them receive your raw motion data, your name or your onboarding answers.

8. Retention

Data on your device stays until you delete it, in the app or by removing the app. Anonymous analytics events are retained according to PostHog's standard retention policy. Subscription records are retained by Apple and RevenueCat according to their own policies and applicable tax rules.

9. International transfers

All posture analysis happens on your device. The anonymous analytics events in section 4 may be transferred to and stored on servers operated by PostHog, and subscription records by RevenueCat, including in the United States, under those providers' own terms and safeguards.

10. Your rights

Because Pillar has no accounts, we generally cannot connect any data to a named individual, which limits what we can look up on request. What you can do:

If you are in the European Economic Area or the United Kingdom, you have the rights of access, rectification, erasure, restriction, portability and objection under the GDPR. Our lawful basis for the analytics in section 4 is legitimate interest in maintaining and improving the app; for processing your purchase, performance of a contract. If you are in California, we confirm that we do not sell or share personal information as those terms are defined by the CCPA/CPRA, and we do not offer financial incentives for personal information.

11. Children

Pillar is not directed at children under 13, and we do not knowingly collect data from them. The onboarding asks for an age range only to phrase its own copy; that answer stays on your device.

12. Security

Everything the app stores lives in your iPhone's own protected app container, covered by iOS device encryption. Data in transit to PostHog and RevenueCat is encrypted with TLS. No system is perfect, and we cannot guarantee absolute security.

13. Changes to this policy

If we make material changes, we will update the “Last updated” date above and, where practicable, say so in the app. Continuing to use Pillar after a change takes effect means you accept the updated policy.

14. Contact

Questions about this policy or about your data: glowdapp@gmail.com. We answer in English or Ukrainian.