Notifications from the App

24 September 2026 - Terms of Use and Privacy Policy update (effective 1 October 2026)

To reflect new and changed features, we will revise our Terms of Use with effect from 1 October 2026. The Terms of Use are available in Japanese only, and the Japanese text prevails. The main changes are:

  • Article 1 (About the App) now covers reading puzzles from photos, solving puzzles yourself, and hints.
  • The former Article 3 (Paid features) has been removed and replaced by Article 3 (Free features and advertising) and Article 4 (Subscriptions). Its provisions on price changes and refunds have moved to Article 4.
  • Article 3 states that the app is free to use and shows ads, that some features become available after you watch an ad to the end (currently hints, reading puzzles from photos and on-device auto-solve), and that subscribers do not see ads.
  • Article 4 sets out the auto-renewal terms and how to cancel, the usage allowance for solving on the server, and that payment and refunds follow Apple's procedures. If you cancel partway through a period, the fee for that period is not refunded pro rata.
  • New Article 5 (Data you enter or import): when you import puzzles from magazines, books or other sources, please use them only as permitted by law (for example, private use), and do not publish or distribute them without the rights holder's permission. Puzzle data is stored on your device, and we are not responsible if it is lost because your device is broken or lost, the app is deleted, or for any other reason.
  • Article 6 (No warranty) now states that we do not guarantee the accuracy of photo reading, hints or auto-solve results. Article 7 (Prohibited acts) now includes improperly avoiding or manipulating ads. Article 9 (Suspension of service) now states that solving on the server may be suspended. New Article 15 (Handling of user information) states that your information is handled under the Privacy Policy.

Because articles were added, former Articles 4 to 12 are now Articles 6 to 14, and former Articles 13 to 15 are now Articles 16 to 18.

We will also revise our Privacy Policy on the same date. The main changes are:

  • You can now choose between "Solve on this device" and "Solve on server" for auto-solve. "Solve on server" (subscribers only) sends the puzzle, its name, the app version and display language, the address for completion notifications and an anonymous user identifier to our server. Solutions are kept for up to one week and deleted once you receive them.
  • The anonymous user identifier is used to accept server solving requests, manage the usage allowance and check your subscription status. The RevenueCat module we use to check purchases uses this identifier as the purchaser ID.
  • Reading from photos can now also read a partly solved board. Images are still analysed on your device only. Hints are also computed on your device and are not sent.
  • The policy now describes what Google services are used for (error reports, usage analytics, authentication, connection checks and notifications), and the ads we show (video ads and banner ads).
  • The data sent under "Sharing puzzle data" is now listed to include your device model and OS version. As before, it is not linked to you, and you can stop it at any time in the Settings screen.

If you use the app on or after 1 October 2026, you will be deemed to have agreed to the revised Terms of Use and Privacy Policy.

18 September 2026 - Auto-solve now runs on your device, and Privacy Policy update

Automatic solving now runs on your device instead of on our server. We have revised our Privacy Policy accordingly. The main points are:

  • Solving happens on your device, and the solutions are stored on your device only. Because solutions are no longer kept on the server, the section on how long solutions are kept has been removed.
  • Only to investigate and improve solving speed, the puzzle you entered and how long it took to solve are sent to us. This is never linked to you. No user ID, advertising identifier, per-device identifier or puzzle name is sent. We do not use it for any other purpose and do not provide it to third parties. You can stop this at any time under "Sharing puzzle data" in the app's Settings screen (no features are restricted if you do).
  • Completion push notifications and the "Retrieve Solutions" menu item have been removed. Solutions now appear on the board as soon as they are found.
  • Automatic solving no longer has a time limit. While it runs, the app shows the number of cells determined, the number of solutions found and the elapsed time, and you can tap "Stop" at any time to take the solutions found so far. The screen stays awake while solving, but closing the app or switching to another app interrupts it.

The Terms of Use are unchanged. Earlier versions of the app continue to use solving on the server as before.

11 September 2026 - Privacy Policy update

We have revised our Privacy Policy to reflect recent changes to the app. The main points are:

  • The app can now read a puzzle from a photo. Images are analysed on your device only. They are never sent outside your device, and we never store them.
  • We now state how long solutions are kept. With a subscription, a solution is kept on the server for up to one week and is deleted as soon as you receive it in the app. Previously solutions were kept for 30 days and could be fetched again; from now on the same solution cannot be fetched twice. Received solutions are stored on your device, so please take care not to delete the puzzle data.

We have also changed automatic solving from a one-off purchase to a monthly subscription. Prices and details are shown on the purchase screen in the app. The Terms of Use are unchanged.