Privacy Policy

Data We Collect

Measurement data — We record heart rate (BPM) and numerical values such as heart rate variability calculated from the iPhone camera, together with the measurement time, and use them to generate art. Data received from Apple Watch is described under “Apple Watch and HealthKit” below.
Account and profile information — We use Firebase Authentication for Sign in with Apple and Google. Authentication uses a Firebase user ID (UID) and account information, such as an email address, supplied by the sign-in provider. On Myaku's server, the UID is linked to an invitation code and pairing information. An optional username you enter and a profile image you select and upload are also stored on the server.
Mood and notes — Any mood or note you choose to add to a record is stored on your device.
Purchase information — We use RevenueCat to check purchase status, restore purchases, and determine access to paid features.

Data We Do Not Collect

Myaku does not access your location or contacts. It does not save or transmit the camera footage or microphone audio itself.

Storage, Sync, and Sharing

Your measurement records, moods, notes, and generated art are stored on your device. You do not need to sign in to keep your own records.

Records created while signed in send numerical parameters such as BPM, heart rate variability, and sound level, together with the measurement time, art type, and art-generation parameters, to our server. This happens whether or not you have a paired partner. If a transfer fails, pending data is stored on the device and retried using the original account. Paired partners can view art generated from this data.

Moods and notes are not included in this server sync or shared with paired partners. They are also excluded from art images and videos exported by the app. Saving to Photos or sharing with another app happens when you choose the corresponding action.

Contact Form

When you use the contact form, we store your email address, optional name, topic, message, language, consent, and submission details in a Cloudflare database to handle your inquiry and prevent duplicate submissions. To limit spam, we use an hourly keyed hash derived from your IP address. The original IP address is not stored in the contact database.

Third-Party Services

We use the following services. Their official information explains how they handle data.

Firebase Authentication — Account authentication. Privacy and Security in Firebase
Apple and Google — Sign-in providers. Apple also handles in-app purchases. Apple Privacy Policy · Google Privacy Policy
RevenueCat — Purchase status and paid-feature access. RevenueCat Privacy Policy
Cloudflare — Running the API and storing synced data, profile images, and contact submissions. Cloudflare Privacy Policy

Camera and Microphone Usage

The camera is used for heart rate measurement, with footage analyzed on the device. The footage itself is not saved or transmitted.

If you allow microphone access, audio captured during measurement is processed on the device to calculate a sound-level value used in art generation. The audio itself is not saved or transmitted. Heart rate measurement still works without microphone permission. The numerical sound-level value is included in the sync described above for records created while signed in.

Apple Watch and HealthKit

The Apple Watch app reads heart rate data from HealthKit with your permission. When you choose to record it, the app transfers the reading's BPM, its actual measurement time, and its record identifier to your iPhone. If the iPhone is not immediately reachable, the transfer may wait until a connection is available.

The iPhone uses the received reading to generate art and create a record. Records created while signed in are subject to the server sync described under “Storage, Sync, and Sharing” above.