Privacy Policy

We don't collect your personal data. There are no accounts, no analytics, no advertising trackers and no third-party SDKs — on the website or in the iOS app. This page explains exactly what that means, including the two places where a request does leave your device, because a privacy policy that skips the inconvenient parts isn't worth reading.

Last updated: 31 July 2026. This policy covers the website at blackjackoddstrainer.com and the iOS app Blackjack Odds: 21 Trainer.

The short version

• We collect nothing. No name, no email, no account, no device identifier, no advertising ID.
• No advertising trackers. There is no Google Analytics, no Meta pixel, no heatmapping, no session recording and no A/B testing tool on any page. Nothing follows you to other sites.
• No cookies are set by this site.
• The iOS app makes no network requests at all. It works fully offline and has nothing to send.
• Nothing is sold or shared — there is nothing to sell or share.

The iOS app

Blackjack Odds: 21 Trainer is entirely on-device. The odds engine, the strategy chart, the counting drills and the progress tracking all run locally, which is why the app works in aeroplane mode.

Your bankroll, drill history, mastery map, cost ledger, session records and settings are written as JSON files inside the app's own Application Support directory. That data never leaves your phone. It is not backed up to any server we control, it is not synced between devices, and we cannot see it. Deleting the app deletes all of it permanently — there is no copy anywhere else, so there is nothing for us to restore and nothing for you to request.

The app contains no analytics library, no crash-reporting service, no advertising framework and no third-party SDKs of any kind. Its App Store privacy label is Data Not Collected.

The website

Every page is static. There is no login, no comment system, no newsletter form and no checkout.

The trainer and the calculators keep your progress — bankroll, hands played, accuracy, settings — in your browser's localStorage, under the key bj21-save-v1. This is storage on your own computer, not a transmission to us: it is never sent anywhere, and we have no way to read it. Clearing your browser's site data for this domain erases it.

Where requests do leave your device

Two, and we would rather name them than let you find them in the network tab.

• Web hosting. The site is served by Cloudflare Pages. Like every web server on the internet, it processes your IP address and browser user-agent in order to deliver the page, and may retain them briefly in operational logs for security and abuse prevention. We don't build profiles from this, and we don't have an analytics dashboard sitting on top of it. Cloudflare's handling of that data is covered by Cloudflare's privacy policy.
• Google Fonts. Our pages load typefaces from fonts.googleapis.com and fonts.gstatic.com. That request necessarily discloses your IP address to Google. We use it purely for typography and receive nothing back. Google's handling is covered by the Google privacy policy. If you would prefer this not happen, a content blocker will stop it and the site will still work in a fallback font.
• Aggregate traffic counts. We may use Cloudflare Web Analytics to see how many people visit which pages. It is deliberately the least invasive option available: it sets no cookies, uses no device fingerprinting, assigns you no persistent identifier and cannot follow you to any other website. We see page counts and referrers in aggregate — never individuals, and never anything tied back to you.

Children

This is a strategy trainer, not a gambling service — it uses play chips and takes no real money — but blackjack is casino subject matter. The site and the app are not directed at children under 13, and we knowingly collect no data from anyone of any age.

Your rights

Rules like the GDPR and the CCPA give you the right to access, correct, export or delete the personal data a company holds about you. We hold none, so in practice there is nothing to request. If you want to erase what exists, it is all on your side: clear this site's data in your browser, or delete the app from your phone.

Changes to this policy

If this ever changes — for instance if analytics or an account system is added — this page will be updated and the date at the top will change. We won't start collecting data quietly and describe it here afterwards.

Contact

Questions about this policy, or think we've got something wrong? Email [email protected].

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