1. Information we collect

In the current version, 4tr collects the following three things:

• The photos you send us so that we can make your song
• A device ID that the app creates automatically (a random string)
• Communication records (access logs)

We do not ask you to register your name, email address, phone number, date of birth, or similar information. There is no account to create.

About the device ID

We use it only to count which songs were made on the same device. When you first launch the app, the app automatically creates a random string, stores it on your device, and sends it along whenever you make a song.

• This ID cannot be used to identify you. It contains no name, email address, device model, location, or similar information, and we do not link it to any other information.
• If you delete the app, this ID is deleted too. If you reinstall the app, you will get a different ID.
• Its only use is to count which songs were made on the same device.

About communication records (access logs)

Communications with the 4tr server are recorded automatically by the platform that runs the server (Google Cloud). These records include:

• IP address
• Browser and OS type
• The page you came from
• The date and time, destination, amount of data, and response time of each communication

They are used for two purposes: investigating problems and blocking extremely frequent repeated access (to protect the server). We do not process these records to identify you.

These records are deleted automatically after 30 days.

To block extremely frequent repeated access, the server keeps IP addresses in memory temporarily, but does not store them (they are cleared when the server is replaced).

2. How we handle photos

• Photos you send: Before sending, the app resizes any photo whose longer side is greater than 1,200 pixels to 1,200 pixels, locally on your device. Photos that reach the server are deleted from the server as soon as the song-making process is finished.
• A single image made by cropping the four photos into squares and arranging them 2×2 (the song's cover): Because it is used in your song list and as the background of exported videos, we keep it and do not delete it.
• Photos are sent and received over encrypted communication (HTTPS).

In short, the original photos you send are not kept, but the reduced, combined image is.

3. Where cover images are stored and who can see them

Saved songs and cover images are kept on Google's cloud in Japan (Tokyo).

To display a song or its cover image, an authentication string issued for each song is required. This string is given only to the device that made the song (anyone who made a song from the same combination of photos receives the same string). Knowing the URL alone is not enough to display a song or its cover image.

However, we cannot fully guarantee that no third party will ever view them. Please avoid using photos you would not want others to see.

4. If a face appears in a photo

If a face appears in a cover image, it is stored as it is, without blurring or any other processing. Whether to use photos that show faces is up to you.

5. What we do not do

• We do not perform face recognition or any processing aimed at identifying individuals.
• The only things we take from photos are general image statistics, such as brightness, saturation, the amount of edges, and the flow of lines.
• We do not show ads, and we do not provide data to third parties for advertising or analytics purposes.

6. Information related to paid plans

If you use a paid plan, payment is made through the App Store, and we do not receive payment information such as your credit card number.

To check whether you have a subscription, we use a purchase management service (RevenueCat). An ID that identifies your device and your subscription status are sent to RevenueCat, but your name, email address, and similar information are not.

7. Retention period and requests for deletion

Songs, cover images, and per-song records (including the device ID the app creates, described in Section 1) are kept in order to provide the service.

You can delete a song yourself at any time from the "Past songs" list in the app. When you do, the song, its cover image, and its per-song record are removed from the server. Songs made with one to three photos before all four photos were in place are deleted along with it.

Because the same combination of photos produces the same song, in very rare cases your song may disappear if someone else deletes that song. Even then, you can make the song again by adding the same photos, although after an app update it may turn out different from before.

Songs made with one to three photos that never reached four are deleted in turn once a certain period has passed.

If you cannot delete a song, please contact us at the address below.

8. Use by minors

Please use the service with the consent of a parent or guardian. The same applies to signing up for a paid plan.

9. Changes to this policy

If we change this policy, we will post the updated version on this page. For important changes, we will also let you know in the app.

10. Contact

For questions about this policy or the service, or to request deletion of stored data, please contact us at:

info@sea-song-label.com

Service

4tr

Provider

feather village coffee (Ryohei Ameda)

Address (in Japanese)

神奈川県川崎市高津区梶ケ谷3-3-2 かけいビル501

Contact

info@sea-song-label.com

Effective: October 13, 2026