Last updated: 23 August 2026

Summary

ArmSound collects nothing about you.

The app makes no network requests to detect, record, or play your motions. Your arm motions and your history stay on your Apple Watch and iPhone. Nothing is sent to anyone, including the developer. There is no account to create.

The one exception is in-app purchase. When you buy or restore, the app talks to Apple’s App Store. This uses Apple’s own mechanism (StoreKit), and the developer never receives your payment details (see “In-app purchase” below).

What is not collected

None of the following is collected, received, or stored:

• Name, email address, phone number, or any contact details
• Location
• Device identifiers or advertising identifiers
• Usage analytics or crash reports
• Contacts, photos, or calendars

What stays on your device

The app works with the following, and none of it leaves your devices.

What	Where	Why
Arm motion waveforms	App storage on the Watch and iPhone	To match your motions and play a sound
Whether a motion fired or not	Same	So you can review recent judgements and correct them with Learn / Ignore
Imported sound files	Same	To assign and play per motion
Settings (groups, thresholds)	Same	To determine behaviour

The Apple Watch and iPhone exchange this data using Apple’s WatchConnectivity. That exchange happens between your two devices and does not pass through any server.

Sensors and health data

The app reads acceleration and rotation rate from Core Motion. This is used only to judge arm motion, and the readings stay on the device.

The app starts a workout session (HealthKit). This exists so that judging and playback keep running when the screen turns off. It is not used to read heart rate or any other health data. The only thing the app writes to HealthKit is the start and end of that session, and no health data is ever sent anywhere.

In-app purchase

Unlocking the paid features uses Apple’s in-app purchase mechanism (StoreKit).

• Apple handles the payment. Your name, card number and address never pass through the app, and the developer never receives them.
• All the app does is ask Apple whether the purchase exists. Apple stores that answer on your device, signed, and the app reads it.
• Nothing about your purchase is sent to a developer server. There is no developer server.
• Only when you tap “Restore purchase” does the app ask Apple to check again.

For how Apple handles payments, see Apple’s own privacy policy.

Sharing with third parties

None. The app contains no third-party analytics, advertising, or SDKs.

Deleting your data

Deleting the app removes all of the above from your device. Within the app you can also delete individual motions, sounds, and judgement history.

Children

No information is collected from users of any age.

Changes

If this policy changes, the date at the top of this page will be updated.

Contact

• GitHub Issues: https://github.com/888man/armsound-support/issues