Privacy policy

Last Known Position, by Made by Eddie (Eddie Ferrer)
Effective: October 27, 2026
Contact: support@lastknownposition.app

In short

• Your progress (ratings, history, settings) is stored on your phone.
• To improve the puzzles, the app can send your puzzle results (moves, times, outcomes) to our server, tied to a random ID created by the app. It never sends your name, email, location, contacts or advertising ID.
• In the closed beta, sharing results is part of taking part. In the public app, it's off unless you turn it on.
• You can delete your shared results at any time in Settings.
• No ads, no advertising or analytics trackers, and we never sell data.

What stays on your device

The app stores the following on your phone only:

• every puzzle attempt: the moves you played, timings and outcomes;
• your ratings, review schedule, streaks and stats, which are worked out from those attempts;
• your settings and whether you finished the tutorial;
• a random install ID, created the first time you open the app. It is not linked to your name, your Google account or your device's identifiers.

None of this leaves your phone unless results sharing is on (below). Uninstalling the app or using Settings → Reset progress deletes it.

Shared puzzle results

To find broken puzzles and set fair puzzle ratings, the app can upload your puzzle results.

What's sent, after each puzzle: the puzzle number, level and version; the outcome and solve time; the moves you entered, with their timing and how you entered them (tapping the board or the keypad); moves the app rejected as illegal; whether you used the replay; when you started (with your time zone offset); the app version, the platform (Android or iOS) and your install ID.

What's not sent: your name, email address, account, location, contacts, device model, advertising ID or settings. Rejected input can only contain chess notation characters, so it can't hold free text.

When it's on:

• Closed beta: sharing results is required to take part. Testers are told in the invitation and when they first open the app.
• Public app: off unless you choose to turn it on when you first open the app. You can turn it off in Settings at any time.

Deleting it: Settings → Delete my shared data deletes every result uploaded with your install ID. You can also email us with the install ID shown in Settings.

Our server sees your IP address when the app uploads, as any internet connection does, but it isn't stored with your results.

Feedback and puzzle reports

If you use Report this puzzle or Send feedback, we receive what you write, plus the puzzle number, level, the moves you played, the app version and your install ID, so we can match the report to the puzzle. If you email us instead, we receive your email address and message.

Crash reports

When the app crashes or hits an error, it sends a report to Sentry, our error-tracking provider: the error and where in the app it happened, the app version, the operating system version and device model, and your install ID. Crash reports don't include your puzzle history, and IP addresses aren't stored with them.

How we use data

Only to run and improve the app: finding broken puzzles, setting puzzle difficulty, fixing crashes and bugs, and answering your messages. We don't use it for advertising, we don't build profiles of you, and we don't sell or share it with anyone except the providers below.

Legal basis (for people in the EU and UK): shared results in the public app rely on your consent, which you can withdraw at any time in Settings. In the closed beta, and for crash reports and feedback, we rely on our legitimate interest in testing and fixing the app.

Service providers

• Supabase: stores shared results and feedback, on servers in the Americas.
• Sentry: crash reports, stored in the United States.
• Google Play and, later, the Apple App Store distribute the app. They handle downloads and payments under their own privacy policies.

These providers process data for us and may store it outside your country, with the safeguards their terms provide.

How long we keep it

• Detailed shared results: about 90 days. After that they're combined into per-puzzle totals (such as solve rate and common wrong moves) that aren't linked to any install ID, and the details are deleted.
• Feedback: until it's dealt with, then up to a year.
• Crash reports: about 30 days, Sentry's retention on our plan.
• Emails: as long as needed to answer you.

Your rights

You can ask to see, correct or delete the data we hold about you, or object to how we use it, by emailing support@lastknownposition.app with the install ID shown in Settings. That ID is the only way we can find your data, since we don't know who you are. Depending on where you live (for example under the GDPR in the EU and UK, or the CCPA in California), you may have further rights, including complaining to your local data protection authority.

Children

The app isn't aimed at children under 13, and the closed beta is for adults. We don't knowingly collect data from children. If you think a child has shared data with us, email us and we'll delete it.

Security

Data is sent over encrypted connections (HTTPS) and stored with providers that protect it to industry standards. No system is perfectly secure, which is one reason we collect so little.

Changes

If this policy changes, we'll update it here with a new effective date, and tell you in the app if the change is significant. We won't start collecting new kinds of data without telling you first.

Contact

Questions or requests: support@lastknownposition.app