Terms of Use

App Keigo 敬語 · version 1.5 · last updated: 24 September 2026

What you get

Keigo 敬語 is an educational app about the Japanese honorific register. Levels 1 and 2 are free in full. A single non-consumable in-app purchase — Keigo Premium — unlocks levels 3, 4 and 5 and covers material added to them later. Version 1.5 adds a separate, optional feature: the Check tab, where a language model assesses a sentence you write for the person you choose to address. It is paid for by the subscription described below.

Purchases and refunds

The app is licensed under Apple's standard licence terms (Licensed Application End User License Agreement). These terms supplement them and cover what applies to Keigo only; where the two conflict, Apple's terms prevail.

Purchases are processed by Apple under the App Store terms. Refunds are handled by Apple, not by the developer — request one at reportaproblem.apple.com. "Restore purchases" re-checks your entitlements on any device signed in with the same Apple Account.

AI Check — auto-renewable subscription

Check is the only part of the app that costs money every time it is used, which is why it is paid for by subscription rather than a one-off purchase.

Everyone gets a free sample every month — currently 5 checks — with or without Premium and without a subscription. The app shows how many are left and when they come back.
More checks come with the AI Check subscription, monthly or yearly. The app shows the price and period before you buy, in your currency. The subscription has a daily and a monthly limit on checks, which protects the service from abuse.
The subscription renews automatically until you turn it off. Payment for the next period is charged to your Apple Account within 24 hours before the current period ends.
Cancelling: in your Apple Account settings (Settings → your name → Subscriptions) or with Manage subscription in the app, at least 24 hours before the current period ends. The subscription keeps working until the end of the paid period.
The subscription does not unlock levels 3–5, and Keigo Premium does not include the subscription. They are two separate products; material you bought once stays yours regardless.
Check needs an internet connection and may be temporarily unavailable — for example during maintenance or an outage at the model provider. The rest of the app keeps working as usual.

The learning content

The scenes, example sentences, translations and explanations are original work and are provided for personal study. They may not be reproduced, redistributed or used to train machine-learning models.

The honorific register is genuinely disputed among native speakers of Japanese — that is a fact about the material, not an excuse. Keigo follows 文化庁「敬語の指針」(2007) and says so plainly where usage is contested. Judging whether a given situation calls for a particular form is yours to do, not the app's. The five levels describe how the material is ordered for learning; they are not examination levels, and the app is not affiliated with, authorized by or endorsed by any body that administers a Japanese-language examination.

Answers in Check

The assessment in the Check tab is generated by a language model and can be wrong — including on points where native speakers disagree. It is a hint, not a teacher's opinion or an exam grade: treat it as a starting point for checking, not as a verdict. A check result does not count towards your progress or reviews.

No warranty

The app is provided "as is". While the content is checked carefully and validated automatically, no guarantee is given that it is free of error. The developer is not liable for damages arising from its use. This does not limit any rights a consumer has under mandatory law.

Your data is your responsibility

Progress is stored on your device only. Deleting the app deletes your progress with it; you can keep a copy with Export progress in Settings. The exception is Check, and only when you tap the button yourself: your sentence and the person you chose are sent to the server. What exactly is kept, and for how long, is set out in the privacy policy.