ilsudoku.it

Cookie Policy

This Cookie Policy explains how ilsudoku.it uses cookies and similar browser storage technologies.

The summary is short: our code sets exactly one cookie, the one that remembers your preference choice. This site’s analytics use no cookies at all.

What Cookies Are

Cookies are small text files that a website places on your device. We also use localStorage, a browser storage mechanism that works similarly but stays on your device and is never automatically transmitted to servers.

Necessary Cookies and Storage

These are essential for the website to work properly and cannot be disabled.

  • cc_cookie (cookie) — the only cookie our code sets. It records your preference choice so the panel is not shown again on every visit.
  • __ph_opt_in_out_… (localStorage) — written only once you have made a choice. It records that choice for our analytics tool so an objection stays in effect. It contains a single character (0 or 1) and no identifier.
  • Game progress (localStorage) — saves the current puzzle state, timer and move history so you can resume later.
  • Daily puzzle progress (localStorage) — saves your progress on the daily challenge for each difficulty level.
  • Theme preference (localStorage) — remembers your chosen colour theme.
  • Language preference (localStorage) — remembers your selected language.
  • Input mode (localStorage) — remembers whether you prefer “digit first” or “cell first” input.
  • Layout preference (localStorage) — remembers your preferred layout (bottom or side controls).

Apart from cc_cookie, all necessary data is stored locally on your device and is never transmitted to our servers.

Analytics — No Cookies

This site’s usage analytics set no cookies and store no identifier. PostHog is configured with memory-only storage: the analytics data itself exists only for the lifetime of the open page and nothing about your activity is written to your device. The same applies to Fathom Analytics, which keeps no identifier of any kind.

The only thing these write to your device is the record of your own choice, once you have made one — the localStorage entry listed above. It exists so that a rejection keeps working, and it holds no identifier and no usage data.

Because we use no cookies for this purpose, the processing relies on legitimate interest rather than consent — but PostHog remains fully refusable: rejecting the “analytics” category in Cookie settings stops it, and the session recording below with it.

Fathom is not stopped by that setting. It keeps no identifier and produces only aggregate counts, so there is no per-visitor state for a cookie preference to govern. The Privacy Policy explains the reasoning and how to object to it specifically.

Crash Reporting — Not a Cookie at All

We use Sentry to be told when the site breaks. It is listed here only to be complete: it stores nothing whatsoever on your device — no cookie, no localStorage, no sessionStorage — so there is nothing for a cookie preference to govern, in any category.

It is also not part of the “analytics” category and is not stopped by rejecting it, because it serves a different purpose: keeping the service working, rather than measuring how you use it. The Privacy Policy explains that reasoning and how to object to it specifically.

Session Recording — Consent Required

If you accept the “analytics” category, we anonymously record about half of visits: clicks, pointer movement and navigation within the game. All text fields are masked, and the gift sudoku pages are never recorded.

It is worth being clear why this feature requires consent: not because it stores anything on your device (it does not — cc_cookie remains the only cookie our code sets), but because of what it records. Watching how a person moves around the page is something we think it is right to ask permission for.

Cookies Set by Cloudflare

The site is delivered through Cloudflare, which sits in front of every request and may set its own technical and security cookies — for example __cf_bm, used to distinguish automated traffic from human traffic. These cookies are set by Cloudflare as our CDN provider rather than by us, are not under our direct control, and are not used for analytics or advertising purposes. See the Cloudflare Privacy Policy.

Managing Your Preferences

You can change your preferences at any time by clicking Cookie settings in the site footer. From there you can both withdraw consent for session recording and object to the anonymous analytics; both take effect immediately.

You can also delete all locally stored data (game progress, preferences) by clearing site data for this domain in your browser settings.