Privacy Policy

App: OtoSignal Morse　/　Last updated: October 4, 2026

This app (the "App") respects your privacy and works to protect personal information. This policy explains what information the App handles and how it is used.

1. Personal information collected by the developer

2. Information stored on your device

• Settings (speed, pitch, volume, color theme, etc.), practice records (completed steps and stars), your best scores in the games, and the phrases you save in "Quick phrases" are stored only on your device.
• They are never sent to the developer's or any third party's servers.
• This information is lost when you uninstall the App or clear its data. It is not carried over by device backups or when you change devices.
• In the App's Settings, you can delete your practice records and reset the settings.

3. Microphone

• The microphone is used on the "Send & Receive" screen (when receiving by sound) and in 2P mode, to hear the Morse sounds played by the other phone.
• The audio is only analyzed on the device, on the spot, for the pitch and length of the sounds, and turned into code and text. Nothing is recorded, saved, or sent.
• The microphone is used only from when you press "Start receiving" until you stop it, or while you play in 2P mode. It is closed while you are sending. It stops when you leave the screen.
• Without microphone permission, you can still use Send, Practice, the Code Chart, and the single-player games.

4. Camera and flashlight

• The camera is used on the "Send & Receive" screen with light (camera), to read the flashing light of the other phone.
• The video is only analyzed on the device, on the spot, for brightness, and turned into code and text. No photos or videos are saved or sent.
• The feature that flashes the rear light when sending only turns the light on and off. It does not take pictures.
• Without camera permission, you can still use every feature except receiving by light.

5. Device permissions

• Microphone and Camera: as described in 3 and 4. Before either is used, the App explains the purpose on screen, then shows the device's permission request.
• Internet: used to show ads. The fonts are built into the App and are not loaded from the internet. Sending and receiving Morse code does not use the internet (it works directly by sound and light).
• The App does not use permissions such as location, contacts, photos and files, or phone.

6. Ads (use of data by a third party)

The App shows ads using Google AdMob, a mobile advertising service provided by Google. For ad delivery, measurement, and fraud prevention, AdMob collects the following information from your device and sends it to Google.

• Device or other IDs — Advertising ID, App Set ID
• Approximate location — IP address (used to estimate your approximate area, at about the city level)
• App activity — number of interactions such as app launches and taps
• App info and performance — diagnostics such as launch time and hang rate

This information is handled under Google's privacy policy, and it is sent encrypted with TLS. The App has no in-app purchases, such as paying to remove ads.

Ads are banners only, at the bottom of the practice course list, the game selection screen, and Settings. No ads are shown while you practice or use Send & Receive, or while you play a game. Full-screen ads are not used.

For how Google handles information, see:

• Google Privacy Policy
• How Google uses information from sites or apps that use our services

You can reset or delete your Advertising ID in your device's Settings > Privacy > Ads. You can also opt out of personalized ads on the same screen.

7. Analytics

The App does not use analytics tools (such as Google Analytics).

8. Children's privacy

The App is not directed primarily at children under 13.

9. Changes to this policy

This policy may be changed as needed without notice. Changes take effect when they are posted on this page.

10. Contact

For questions about the App or this policy, please contact: