This page is a translation provided for convenience. If there is any difference in meaning, the Japanese original prevails.

Privacy Policy

— Privacy Policy

HisatorNotebook (the “App”) sets out below how it handles user information. The App does not incorporate any mechanism whatsoever for ad delivery, access analytics or crash collection. Furthermore, we do not sell any information we obtain to third parties.
Operator Hiroyasu Hisada Our address and telephone number are listed in the Notice under the Specified Commercial Transactions Act.
Contact hisatasan1@gmail.com You may also contact us via “Bug / Feature request” in the in-app menu.
Information sent
simply by launching the App		 When launched, the App automatically collects and sends the following information.
  • An anonymous ID for each device (Firebase anonymous user ID): this is not linked to your name or email address.
  • IP address (unavoidably transmitted as the address for communications)
  • Device country and language settings
  • Date and time of last use
  • Queries for your current plan and your AI usage balance
We do not collect age, gender or date of birth. We also do not collect location information unless you explicitly operate a feature that uses maps, weather or location information.
Information sent
depending on your use		 The following information is sent only when you use the corresponding feature.
  • If you sign in with Google: email address, display name, profile image and language setting
  • If you use cloud sync, sharing or publishing: page content, memos, schedules, and attached images, PDFs and videos
  • If you use AI features: text you enter, page content, text extracted from PDFs, and attached images
  • If you purchase a paid plan: plan, billing start and end dates, coupon code, and AI usage and amounts
  • If you contact us: message body, display name and your current plan
  • Location information for the in-app browser: our server returns your approximate location (to about the city, town or village level).
Information stored
only on your device		 The following is not sent to our servers.
  • Screen recordings and screenshots
  • Results of reading transit IC cards (display and copy only)
  • Cookies stored by the in-app browser (can be cleared in Settings)
Purposes of use
  • Syncing settings, plans and AI balances across devices
  • Providing group sharing, co-editing and web publishing features
  • Running AI features and calculating charges based on usage
  • Processing payments, cancellations and refunds for paid plans
  • Responding to inquiries
  • Preventing misuse (such as limiting the number of submissions)
We do not use information for ad delivery or behavioral targeting.
AI features When you use AI features, the text you enter, page content, text extracted from PDFs and attached images are routed through a relay server operated by us (api.hisator-notebook.com, running on the infrastructure of Cloudflare, Inc.) and sent, using an API key held in our name, to one of the following.
  • Google LLC（Gemini API）
  • OpenAI
  • Anthropic PBC
The relay server does not store the body of submitted content or responses. It records only the total usage (number of tokens and amount) for each user. Handling by each AI provider is governed by that provider's terms. You do not need to provide your own API key from an AI provider to use the AI features.
Contractors We entrust the handling of information to the following businesses.
  • Google LLC: authentication, database (pages, schedules, attachments) and file storage
  • Cloudflare, Inc.: infrastructure for running the relay server, storage of subscription information and usage, and storage of published pages
  • Stripe, Inc.: payment processing (Windows and web versions)
  • RevenueCat, Inc.: subscription management (Android and iOS versions)
We provide the anonymous ID to Stripe and RevenueCat in order to match purchases. Card information never reaches us.
Services your device
connects to directly		 The App connects to the following directly from your device, without going through us (we do not receive the content).
  • Open-Meteo (Switzerland) / OpenStreetMap Foundation: locations selected in the weather feature
  • Google (YouTube): retrieving titles and thumbnails of saved videos, and search
  • Wikimedia Foundation, DuckDuckGo, Inc., DeepL SE: research and translation features
  • Your device OS's speech recognition: voice conversations in AI conversation practice (on Android, Google's system is used in many cases)
  • All sites you open in the in-app browser
Provision to third parties
in foreign countries		 All of the above businesses are located outside Japan.
  • United States: Google LLC, OpenAI, Anthropic PBC, Stripe, Inc., RevenueCat, Inc., Cloudflare, Inc., DuckDuckGo, Inc.
  • Germany: DeepL SE
  • Switzerland: Open-Meteo
For information on each country's personal information protection system and each company's protective measures, please refer to the materials published by each company.
Retention periods
  • Cloud sync (Max plan): pages and attachments in the cloud are automatically deleted 30 days after cancellation (on the Free and Pro plans, data is stored only on your device).
  • Pages published to the web: these automatically expire after the period you specify (7 days by default, up to 30 days).
  • Account information (anonymous ID, display name, country, language, plan, usage): retained until you request deletion.
  • Inquiry content: retained as a record of our response.
Disclosure, correction and deletion If you wish to request the disclosure, correction, deletion or suspension of use of information we hold, please contact us at the contact details above. We will respond after verifying your identity. At present, the App has no feature for deleting your account. If you wish to have it deleted, please contact us. Note that you can export your own notes (JSON / .hnmap / HTML / PDF, etc.) within the App at any time.
Security measures Communications are encrypted using TLS. Access to data stored in the cloud is limited to users who have joined the shared group. Authentication information stored on your device is kept only in the App's storage area on the device and is not sent to our servers. Pages created with the co-editing and web publishing features can be viewed by anyone who knows the code or URL. Please handle them with care.
Use of identifiers We do not use identifiers for advertising purposes. We use the following identifiers to provide our features.
  • An anonymous ID issued for each device (retained until the App is deleted)
  • The same ID, provided to Stripe and RevenueCat in order to match purchases
  • Cookies set by sites you visit in the in-app browser (can be cleared in Settings)
Use by children The App does not verify users' ages and does not intentionally collect personal information from children. The App includes a browser feature that does not perform filtering and features for sharing with other users. If a parent or guardian becomes aware that their child has provided personal information through the App, please contact us at the contact details above. We will verify the matter and delete the information.
Revisions to this policy This policy may be revised in line with changes in laws and regulations or the addition of features. If we make important changes, we will announce them in the App or on our website.
Established: August 28, 2026