Privacy policy

Effective 14 September 2026. Applies to the Hark iOS app ("Hark", "we").

Hark is built so that your hearing and vision results never leave your phone.

What Hark stores, and where

Your profiles, check results, the headphones and volume recorded with each result, your first name and your settings are stored in a file on your device only. There is no account and no Hark server that receives them. Deleting the app deletes them; Settings › Delete all my data does the same without deleting the app.

Apple Health

If you tap "Save to Health" on a calibrated hearing check, Hark writes that audiogram to Apple Health on your device. Hark may read audiograms already in Health to show them beside yours. Hark never writes to Health automatically and never sends Health data anywhere. Health data is governed by Apple's Health privacy terms.

TrueDepth face data and the front camera

Information collected. During the optional eye chart, Hark uses Apple's ARKit face-tracking API to read the live three-dimensional position of a detected face relative to the camera. Hark converts that position into a single face-to-screen distance in metres. Hark does not collect or retain camera frames, photographs, video, depth maps, face mesh or geometry, landmarks, expressions, identity, a biometric template, or Face ID data.

Purpose and use. The live distance is used only to show whether the phone is near the one-metre test distance and to draw the eye-chart letter at the physical size appropriate to that distance. It is not used for face recognition, identification, authentication, advertising, analytics, profiling, or any purpose outside the eye chart. If face tracking is unavailable or declined, the user can continue with manual distance confirmation.

Storage and retention. ARKit's face anchor and Hark's smoothed live distance exist only in memory while the eye chart is running and are discarded when tracking stops or the chart closes. If the user completes the chart, the final numeric viewing distance in metres may be stored on the device with the result so the measurement conditions remain visible. It is not an image, face model, or identifier. That local result remains until the user deletes the result, uses Settings › Delete all my data, or deletes the app.

Sharing and disclosure. No TrueDepth face data, camera data, live distance, or stored viewing-distance result is transmitted to Hark, RevenueCat, PostHog, any server, or any other third party. It is processed on the device only. Hark does not sell face data and does not share it for any purpose.

Microphone

During the optional four-second room check before a hearing check, Hark uses the microphone to compute a coarse room-level estimate in memory. Hark does not create or retain an audio recording and does not transmit microphone data. If the check is completed, only the numeric room-level estimate may be stored on the device with the result until that result, all app data, or the app is deleted. The user can skip the room check or decline microphone access and still use every hearing check.

Purchases

Subscriptions are processed by Apple. Hark uses RevenueCat to validate purchases and manage subscription status; RevenueCat receives an anonymous app-user identifier and Apple's purchase receipt, and no health data. See RevenueCat's privacy policy.

Anonymous usage counts

Hark records anonymous usage events (for example "a hearing check was completed", "the paywall was viewed") with PostHog, hosted in the EU, under a random identifier that is not linked to your name, your Apple Account or your results. The events tell us which screens work and which do not. No result values, names or Health data are included. You can rotate the identifier in Settings › Reset my anonymous ID. Hark does not use advertising identifiers and does not track you across apps or websites.

Notifications

Re-check reminders are local notifications scheduled on your device, only after you allow them. They are never used for advertising.

Children

Hark is rated 12+ and is not directed at children under 13. A parent may create a household profile for a child; the data stays on the parent's device.

Your rights

Because your results never leave your device, there is nothing for us to export or erase on your behalf — you hold the only copy. For anything about the anonymous usage data, write to us and quote your anonymous ID from Settings.