Privacy Policy

Effective date: October 1, 2026

This Privacy Policy applies to the language-learning apps and websites operated by ai-speeds — including Kototabi ことたび (Japanese), Mando (Chinese), Wordwing (English), LingoVoya (French), Amigo (Spanish), Ciaobello (Italian) and Bossa (Portuguese) — on the web, iOS and Android (the "Apps").

The short version

• We do not require an account. No name, email or password is ever asked for.
• Your learning progress is stored locally on your device, not on our servers.
• The free version of some native Apps is supported by ads (see "Advertising" below). Pro (paid) users see no ads. Our websites show no ads.
• We do not sell your data.

Data stored on your device

Learning progress (words learned, review schedule, quiz mistakes, streaks, settings such as language and theme) is saved only in your device's local storage. It is not uploaded as a whole — the only exceptions are the two features described below ("Feedback and anonymous quality signals" and "Invite codes") — and deleting the App deletes this data.

Feedback and anonymous quality signals

• Feedback you send. When you use "Feedback / report an error", we receive your message, the tag you picked, the word or grammar point it is about, the app version, device type, screen size and interface language, so we can find and fix the problem.
• Anonymous quality signals. When you answer a quiz question wrong, the App sends which word it was, which option you chose and the question type. We use these only to find confusing or incorrect content (for example, two answers that are both right). They carry no name, account or advertising identifier. This is on by default and can be turned off in Settings ("Help improve content").
• Offline feedback is kept on your device until it can be sent. Feedback records are kept for up to 24 months and are not shared or used for advertising.

Invite codes

Some native Apps (starting with Kototabi) let you invite friends with a code. A friend who enters your code gets a few days of free access to all content; once they have studied on a few days, you get a reward too. This is free — nothing is sold or charged. To run it and prevent abuse:

• When you open the invite screen or enter a code, the App sends a device identifier to our server. We store only a salted one-way hash of it (never the identifier itself), together with the invite code, the time, and a hash of the first part of your IP address.
• If you entered a friend's code, for the following 14 days the App also sends the dates on which you studied, so we can tell whether the invitation led to real learning. Nothing about what you studied is sent.
• This data is used only to issue invite rewards and to stop abuse. It is not used for advertising, not linked to your name or any account, and not shared.
• Records are deleted automatically after 13 months. To delete them sooner, contact us (below) and tell us your invite code.

In-app purchases

Purchases in the native Apps are processed by Apple App Store or Google Play, and managed through RevenueCat, our subscription-management provider. For this purpose, an anonymous random app user ID, device type and purchase history are processed to validate and restore your purchases. This data is not used for advertising or tracking, and is not linked to your identity. Payment details (card numbers, billing address) are handled entirely by Apple or Google and never reach us.

Notifications

If you enable daily study reminders, notifications are scheduled locally on your device. No notification data is sent to any server.

Audio, images and web requests

The Apps load static content (word audio, illustrations, grammar data) from our servers. These are ordinary web requests; standard server logs (IP address, timestamp, requested file) may be retained briefly for security and operations, and are not used to profile users.

Advertising

Some of our native Apps (starting with Kototabi on iOS) show ads served by Google AdMob to keep the free version free. Ads appear only in limited places (an optional "watch an ad to unlock" button and an occasional full-screen ad between study sessions). Pro subscribers and lifetime purchasers see no ads.

• To serve and measure ads, Google may process your device's advertising identifier (e.g. Apple's IDFA, only if you allow tracking), IP address, and coarse device information. See how Google uses data.
• On iOS, Apple's App Tracking Transparency prompt asks whether to allow tracking. If you decline, you still see ads — just less personalized.
• In the EEA, UK and Switzerland, a consent dialog is shown before any personalized ads, and you can decline or manage your choices there.
• Ads are restricted to a general-audiences ("G") content rating.
• Apps and platforms not listed above, and all of our websites, currently show no ads.

Analytics and tracking

The Apps contain no third-party analytics SDKs. No cross-app tracking takes place except as described under "Advertising" for ad-supported Apps, and only with your consent where required.

Children

The Apps do not knowingly collect personal information from children, and are not directed at children. Where ads are shown, they are limited to a general-audiences content rating.

Changes

If this policy changes, the updated version will be posted at this URL with a new effective date.

Contact

Questions? Email tangzy09@gmail.com.