Privacy Policy

Operator

The operator is Sub10Lab, based in Japan. Inquiries are accepted at the contact address at the end of this page.

Data Stored on Your Device

Your practice records and settings are stored on your device (in your browser for the web version and in the app for the app version). They are not sent to Sub10Lab's servers.

When you connect a smart cube, its MAC address is stored on your device alongside your records to speed up future connections. It is not sent to Sub10Lab’s servers. You can remove it with “Full reset” in Settings.

To find and connect smart cubes and smart timers, the web version uses your browser’s Bluetooth feature, and you choose the device on the browser screen. The app version requests permission to use Bluetooth (on Android, “Nearby devices”) and uses it only to find and connect smart cubes and smart timers. The Bluetooth connection does not send device names or recorded times to Sub10Lab. It does not request permission to use device location (such as GPS), and it does not collect device location. The country used for usage statistics is determined from connection source information received from Cloudflare, as described in Section 06.

Records leave your device only when you export them from Settings or copy the output with “Analyze with AI” in the Records tab. The app version passes exported files to the share sheet. You choose where to send an exported file and where to paste copied content. The app does not send the copied content.

Clearing browser data in the web version or deleting the app version removes saved records and settings. However, device backups or migration when you change devices may restore records and settings from the app version.

Usage Statistics

To understand how many people use the app and how much its features are used, this app sends the following information.

• That the app was used, once a month
• That the output was copied with “Analyze with AI” in the Records tab (only the number of copies is sent; the output content is not sent)
• Information the browser or app adds automatically (the User-Agent). It is used only to determine the OS, browser type, and whether the web or app version is used; the original value is not stored

The web version sends this information unless you turn it off in Settings. The app version sends it only if you select “Send” on the first screen shown when you first open it; nothing is sent until you make that choice.

The destination is the sub10lab.app server.

Practice records, times, your name, your email address, and numbers used to tell users apart are not sent.

So that the fact the app was used is not sent more than once in the same month, the month it was sent (in the form 2026-09) is stored on your device. Entries from 13 or more months ago are deleted the next time you open the app.

The above is published in accordance with the external transmission rules of the Telecommunications Business Act of Japan.

Turning Off Sending

Turning off “Send usage statistics” on the Settings screen stops sending immediately. The switch also lets you change at any time what you chose on the app version’s first screen. Turning it back on resumes sending in the web version the next time you open it, and in the app version after you quit and reopen it.

What Is Recorded on the Server

What is recorded is the month of use, the type of action, the country, the OS in use (including whether the web or app version is used), and the browser.

Previously, the selection of a tab or button and the names of the screen and the group or feature that were selected were also recorded. Sub10Lab has stopped recording them and has deleted the counts already recorded.

No record of individual visits, or of the time they happened, remains.

Counts for months that are 25 or more months ago are deleted from the server.

Because of the database recovery feature of the delivery provider, deleted counts remain for up to 30 days after deletion.

Country, OS, and browser counts are used to decide which languages to support and which environments to use for testing.

Distribution Providers

Cloudflare is used to deliver the web version and operate the server that receives usage statistics. As with any website, your IP address is passed to the delivery provider, but Sub10Lab does not store it.

The country is determined from information received from Cloudflare.

The app version is distributed through the App Store (Apple) and Google Play (Google). Each store handles downloads and the information it collects under its own terms and privacy policy. The store operators are not providers contracted by Sub10Lab for distribution through their stores.

The only external connection initiated by the app version as part of its features is sending usage statistics. Inquiries are sent from your email app. External links connect to their destination when opened.

The operator receives the following from each store:

• Aggregated figures such as installation counts, including counts by country or region, device model, and OS version. They do not include information that identifies users
• Reports of problems such as app crashes. They are based on reports from people who have allowed diagnostic information to be shared with Apple or Google in their device or store settings. Reports include the device model and OS version, but no information that identifies users
• Reviews and ratings. The reviewer’s display name and text are public in the store, and the operator can read and reply. Depending on the store, the device model and app version may also be shown

Handling of Inquiries

When you send an inquiry, we receive your email address, the body of your message, and information attached to email automatically, such as the date and time it was sent. We use this to reply and to check past correspondence.

Receiving, storing, and replying to email is entrusted to Cloudflare, Google, and Resend (all located in the United States). Messages are deleted once the period needed for replying has passed.

For inquiries in languages other than Japanese, Sub10Lab uses an AI service from a U.S. provider to translate them and prepare draft replies.

Sharing with Third Parties

We do not pass personal information to others without your consent. The providers named in Sections 06 and 07 are businesses in the United States. Store operators are not providers contracted by Sub10Lab for distribution through their stores.

The United States has no single nationwide law equivalent to the Act on the Protection of Personal Information of Japan. Personal information is covered by federal laws for particular sectors and by the laws of each state. What each provider does to protect the information is described in the privacy policy and the security pages that the provider publishes.

Sub10Lab has a data processing agreement with Cloudflare, which receives the usage statistics sent by the app, and requires Cloudflare to provide protections at least equivalent to those in this policy.

Sub10Lab encrypts communications with HTTPS and does not include information that identifies users in server counts. Only the operator accesses the accounts used for the server and inquiry email, which are protected with two-factor authentication.

Information and inquiries handled by this app are processed in Japan, where the operator is based, and in the United States, where the contracted providers are based.

By using this app and by sending an inquiry, you are treated as having consented to your information reaching these contracted providers in the United States. Usage statistics can be stopped as described in Section 04, and practice features remain available even when sending is stopped. If you do not consent, stop sending usage statistics or refrain from using the app and sending an inquiry.

We may publish aggregate figures, but they do not include information that identifies an individual.

If you would like to know more about the measures these contractors take, please contact us at the address below.

Contact

support@sub10lab.app

Replies may take a few days.

Sub10Lab also accepts, through this contact, the following requests about the personal information it holds, free of charge:

• confirmation of whether personal information is being processed and access to its contents
• correction
• deletion, anonymization, or suspension of use
• provision of personal information to transfer it to another service
• information about the parties to whom personal information was provided
• objection to use and withdrawal of consent

The user may also file a complaint with the data protection supervisory authority in their country or region of residence (ANPD in Brazil, CNIL in France, and CAI in Quebec).

The person responsible for protecting personal information is the operator of Sub10Lab. Complaints about the handling of personal information are also accepted through this contact.

Please also use this address if you have something you want to check about this policy.

Use by Children

Sub10Lab is not designed primarily for children under 13. There is no age restriction on use. Information sent does not include names or numbers used to identify users. A parent or guardian can turn off “Send usage statistics” on the Settings screen to stop sending. Children should talk with a parent or guardian before sending an inquiry.

Changes to This Policy

We update the date on this page when we make changes. The latest version is this page on sub10lab.app. Depending on the version of the app you have installed, this page opened inside the app may be out of date.

Established: 2026-09-16

Revised: 2026-11-02